No drug has been found which will influence the fatal course of East Coast Fever or retard the multiplication of Theileria parva in the blood of the affected cattle.

The drugs which were tried with negative results were Trypanblue, Congo red, Tryposafrol, Creosote and Oleum copaivae, Arsacetin, Soamin, “606,” Emetine hydrochloride, Mercury salicylate, Mercury succinimide, Quinine bihydrochloride and hydrochloride, Ethylhydrocupreine, Ammonium fluoride, Potassium iodide, Sodium salicylate, Calcium lactate, and Nuclein.

All of our animals died—18 treated and 3 untreated—and showed typical lesions at autopsy. They were all infected by means of ticks (Rhipicephalus appendiculatus) which had fed on infected cattle as larvae and nymphs and been placed on the experimental animals as nymphs and adults respectively.

The increase in the number of parasitized red blood corpuscles, but for slight irregularities, proceeds continuously night and day until the animal dies. We have not as yet observed a case ending in recovery.

The accompanying table gives a summary relating to each experimental animal (except XII): the number and kind of ticks which produced infection, the incubation period, the time when the parasites appeared in the peripheral blood, the time when the animals died, and the maximum percentage of parasitized blood corpuscles observed during the course of the disease. The days are all reckoned from Day 1 when the infective ticks were placed upon the cattle.

I was much interested in the paper on Herpetomonads in mice in the June number of Parasitology (Fantham and Porter, pp. 128–132). In 1904 or 1905 when working at trypanosomiasis at Khartoum I came across a flagellate in the peripheral blood of a gerbil (Gerbillus pygargus) which was clearly not a trypanosome and the nature of which I was unable to identify.

Through the courtesy of Dr Hans Gadow I have had the opportunity of examining a number of skins of five species of Apteryx in the collection of the Cambridge University Museum. From these I have collected at least three species of Mallophaga, which I find to belong to the genus Rallicola. These are described below, with some discussion of the genus to which they belong, and of the significance of the occurrence of that genus upon Apteryx, from which no Mallophaga have previously been recorded.

Habitat and Record. The animal under consideration, a parasitic member of the Copepoda, and belonging to the family Lernaeopodidae, occurs commonly on the males, and much less frequently on the females, of Scyllium canicula. The point of fixation is just outside the cloaca, between the pelvic fins, the parasite remaining attached permanently by the second maxillae to the tissues of the host, and occasionally even to the claspers, on their sides, preferably in the groove. I have several times found as many as six specimens on one host (Fig. 1), while three or four is a usual number.

Introduction. In a previous paper (1914, p. 217) I gave, in tabular form, the features which serve to distinguish the two genera Calliobdella van Beneden and Hesse 1863, and Trachelobdella Diesing 1850, which Johansson 1898, pp. 672–675 has also given reasons for distinguishing.

The respiratory system in Mallophaga has not hitherto been described in detail. Kellogg (1896, p. 45) gives the disposition of the main trunks in Tetrophthcdmus, together with a figure; Snodgrass (1899, p. 170) adds nothing to Kellogg's account; Fulmek (1907) dismisses the tracheal system with a paragraph; Shipley (1909) gives a detailed figure for Goniodes tetraonis which is neither complete nor altogether exact; and Mjöberg (1910), although devoting several pages of his morphological section to the respiratory system, is chiefly concerned with the occluding apparatus of the stigmata. He does, however, figure the main trunks in Eutrichophilus, and the occluding apparatus in Gyropus ovalis; and makes certain general statements which may be summarised as follows:

While engaged in experimental researches on the introduction of insect flagellates, belonging to the genera Herpetomonas and Crithidia, into vertebrates, we have recalled to mind some former observations of ours made in 1909. When examining the blood of mice artificially infected with the spirochaetes of relapsing fever in the Quick Laboratory, Cambridge, we observed flagellates in the peripheral blood of the mice. These flagellates, which were scanty, were studied in fresh preparations by us and drawings of the organism were made with the camera lucida. Some of these drawings are now reproduced, together with others made by us subsequently. The flagellates were also observed by Professor Nuttall and his laboratory assistant, Mr B. G. Clarke, and we were unanimously agreed that the flagellates belonged to the genus Herpetomonas, or Leptomonas as some have since preferred to call it. The significance of the presence of herpetomonads in the blood of mice was very puzzling at the time, and pressure of other work prevented the subject being followed up. During 1911 and 1912, these flagellate organisms have been seen by all of us, but they were always evanescent and could not be found in fixed and stained preparations. The parasites were seen on different occasions in three mice altogether.

Female (Fig. 1): Colour: scutum, basis capituli, coxae, distal parts of femur and proximal portions of tarsi and intervening articles are blackish brown, the remaining hard parts shading to yellowish-brown. (Dorsal aspect) Body (partly gorged) short and broad. Scutum about as long as broad, 0·87 × 0·85 mm., very slightly emarginated, with rounded scapular angles, antero-lateral borders almost straight, lateral angles situated at the anterior third of the length, posterior border rounded; cervical grooves deep, far apart, but slightly concave outwardly and slightly divergent, fading near the postero-lateral borders; surface glossy, somewhat rugose; punctations few, mostly fine. Capitulum with base roughly equilateral-triangular, short pointed cornua and sinuous dorsal ridge; porose areas not depressed, subcircular, near ridge, the interval less than their width and hollowed. Palps slender, article 1 small, articles 1–2 almost fused, broadest at the distal third of article 3 which is rounded distally; (Ventral aspect) hypostome club-shaped, 4|4 merging to 3|3 and 2|2 posteriorly where the median unarmed ridge broadens, teeth sharp, 12 per external file; basis capituli constricted where the short pointed recurved auriculae arise, posterior margin straight with rounded angles. Venter: vulva between coxae II; anal grooves form a small closed ring situate near the posterior border; spiracle ovoid, macula central. Legs slender; coxa I with short internal and stout external spur; stout external spurs on coxae II–IV progressively decreasing in size; trochanters with slight spurs; tarsus 4 tapering gradually, the distal pseudo-article about thrice as long as the basal; pads large but shorter than the claws.

This communication is the first of a series dealing with Mallophaga from Australian marsupials. We had hoped to prepare a single monographic work on the Family Boopidae, but the carrying out of this plan has been prevented by a variety of causes, and we think it advisable to publish piecemeal the notes and descriptions that we have accumulated during the last six years. There has of late years been a recrudescence of interest in the Mallophaga, and a considerable number of students are now investigating the group. Little has been published upon the very distinct family which is characteristic of Australian marsupials, and it is important that students of the group should have diagnoses of the family, sub-families, and genera, based upon an ample material, which includes all the known species, with a single exception, and more than an equal number of undescribed new forms. Such a material is at our disposal. Apart from our own collections, Mr A. S. Le Souëf has very kindly transferred to us all his Mallophaga from marsupials, including his types.

An examination of a considerable number of specimens of larval Ascarids from the peritoneal tissues of marine fishes has led me to the conclusion that the great majority of these young nematodes are referable to a single species, Ascaris capsularia Rud. The older descriptions of this form are inadequate and superficial, and even by the more recent writers it appears to have been assumed that, as a larval form, it was impossible, or not worth while, to define it more precisely. I believe, however, that by paying attention to the internal structure it is possible, even at this early stage, to discover characters of specific importance. The imperfect recognition of these characters has led, it appears, to considerable confusion, and to the inclusion in the species of some forms which should be regarded as specifically distinct. A full synonymy and bibliography has been given by Stossich (1896, pp. 55–57) and it is unnecessary here to review the literature in detail. It is desirable to point out, however, that some even of the comparatively recent descriptions intended to refer to A. capsularia seem, in reality, to belong to some other form. Thus É. Blanchard (1849) describes and figures under the name of A. salaris a small form, 20–35 mm. in length, having three lips already visible, a lateral caecum at the base of the oesophagus and female genital organs already developed.