Nine attempts to infect kittens directly with E. histolytica macacorurn by means of amoebae (per anum) or cysts (per os) in the faeces of 2 M. sinicus (Polo and Susanna) and 1 M. rhesus (Jacko), were wholly unsuccessful. Four similar experiments with cysts (per os) from another M. sinicus (Bonar) gave 2 positive (Kittens 28 and 31) and 2 negative results.

Attempts to transmit strains of E. histolytica macacorum from one species of Macacus to another have been uniformly successful.

A strain (D.) of E. histolytica, derived from a man suffering from acute amoebic dysentery, has been cultivated in vitro continuously for 5½ years.

(i) The fact has been confirmed that strains of E. histolytica which, when newly isolated, are infective for kittens, may lose this infectivity after continued cultivation in vitro.

The histological changes in the gut of Chrysops silacea during the digestion of blood are the same as those described by Cragg in Tabanus.

Digestive enzymes are confined to the posterior half of the mid-gut. They comprise an active invertase, a weak amylase and an active tryptase and peptidase. These results are compared with those in Glossina and Calliphora.

The functions of the crop are discussed.

It is presumed that the majority of investigators who dissect anopheline mosquitoes for the purpose of detecting the parasites associated with malarial fever are not concerned with the finer details of anatomical relationships. Nor do they take the time to completely isolate the two acinus glands with the accompanying normal six lobes. This latter is assumed not essential in a search for protozoan organisms, as the sporozoites may be found in the torn portions of the acinus material as well as in the muscular tissue and mounting fluid in which the dissection is made.

The description of the species is made from specimens mounted on slides, which were given to me by the late Dr J. Waterston for examination. As all the specimens were flattened and very much distorted by the pressure of the coverslips, it was impossible to determine whether they belonged to one of the known species. Permission having been received for their remounting, the following method was adopted. The slide was placed in xylol and, after the Canada balsam had dissolved, the specimen was transferred to fresh xylol and then to absolute alcohol. In this medium the wings were detached and, after being cleared in oil of cloves, mounted on a slide. The wingless body was passed through spirits of diminishing strengths to water, and then to caustic potash, and boiled. During boiling the specimens become soft and acquire their natural form. If any parts of the body are still distorted after the boiling they may be restored to their natural position with two dissecting needles. This method of remounting gave a very satisfactory result, although the specimens had been mounted more than 10 years. The further manipulation, together with the morphology of the genus, have been described elsewhere (Jobling, 1930).

Since I published (1925) a description of this interesting new species of a Caryophyllaeid, Woodland (1926) has suggested that the bodies which I described as post-ovarian vitellaria (1925, p. 233, fig. 2, p.ov.vit.) are in reality ovarian follicles, and that, therefore, the worm is a Lytocestus and not Caryophyllaeus. Southwell in his papers (1928 and 1930) has embodied my original description of this worm and has concluded the description by referring to Woodland's remark regarding the post-ovarian vitellaria, without definitely assigning the species to the genus Lytocestus. With additional material at my disposal, it was possible to re-examine its anatomy, and I have found that the bodies described and figured by me as post-ovarian vitellaria are in reality ovarian follicles. I also take this opportunity of publishing a more complete and, I hope, a more accurate description of its general anatomy.

The larval trematodes described in this paper were obtained from fresh-water molluscs collected from Rostherne Mere and a pond near Ashley, both in Cheshire. Rostherne Mere is a large sheet of water and carries an extensive fauna, vertebrate and invertebrate. The molluscs were collected from various fixed positions in the littoral region, and this method has confirmed previous observations (unpublished) in other stretches of fresh-water on the variation in the distribution and localisation of infected molluscs. How far this may be related to movements of the final host or to physical factors affecting the migration of the molluscs is at present uncertain; further observations are being made in an attempt to elucidate this problem. The molluscs were isolated in the laboratory in 3 × 1 glass specimen tubes, when the infected specimens were easily seen by the swarming of the cercariae, and all observations (including measurements) were made on these living, fully developed cercariae. Infected snails were later crushed in physiologically normal saline in order to obtain living sporocysts or rediae for examination. Measurements are, of necessity, only approximate owing to the slight pressure exerted by the weight of the cover-glass and the great powers of contraction and extension of these larval forms. Neutral red was used as an intra vitam stain; it also inhibits movement. Of the five species described four are new, the fifth, for which a further stage in the life history is described, being little known and not previously recorded for this country.

I am indebted to my friends, Messrs M. A. Moghe, of the College of Science, Nagpur, and W. V. Nene, Officer-in-charge of the Time-Ball Observatory, Rangoon, for the material described in this paper. The trematodes were obtained by the former from the duodenum of Uromastix hardwickii (the spinytailed lizard) brought to Nagpur from Northern India, and Mr Nene gave me the tortoise, Batagur baska, which was found to be heavily parasitised with nematodes, along with two flukes. In both instances the trematodes proved new to science.

Habitat and Record. By the courtesy, and at the request, of Louis Page I have examined a specimen of Pennella ♀ from the Muséum National d'Histoire Naturelle, Paris, taken at Concarneau, Brittany, on 22. vii. 30, embedded in the skin of an albacore, Germo alatunga (Gmelin).

It is now slightly more than 60 years since Piaget described as Haematomyzus elephantis an extraordinary insect found by him living as an ectoparasite upon an African elephant in the Zoological Garden of Rotterdam. The insect was considered by its describer to be a sucking louse, and this assignment has been accepted by almost all of the few entomologists who have since been privileged to examine specimens. Walker, who in ignorance of Piaget'os work, redescribed the species as Idolocoris elephantis, regarded it as constituting a new family of Hemiptera Heteroptera near the bed bugs. Since that time no one has questioned the belief that it is a sucking louse and for it Enderlein named a family, the Haematomyzidae, in the Anoplura.