ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 3<">1 



membrane. Three layers of materials can be segregated — a cap of oil 

 drops, a clear protoplasmic layer, and a layer of mitochondria. Normal 

 division figures occur in spite of the redistribution of materials. 



Blood-Sucking Muscid Larvae.* — E. Roubaud calls attention to 

 some of these remarkable forms. — 1. There are haeinophagous parasites 

 of man, notably Auchmeromyia luteola, the larva of which, " ver des 

 cases," is attracted from the soil of huts by the warmth of the body of 

 sleepers. It applies to the skin the free margin of its first post-cephalic 

 segment, and then retracts the pseudo-cephalon, so that adhesion is 

 effected. The piercing of the skin is due to successive scarifications 

 effected by the buccal hooks. The suction is due to the movements of 

 the piston of the pseudo-cephalon. The larva keeps itself erect during 

 the process, the posterior end being quite free. When it is gorged with 

 blood and has a red colour, it falls off on to the ground. It cannot 

 pierce clothes. It can endure fasting for a long time. 2. There are 

 haeinophagous larvae parasitic on Mammals with naked skin, the aard- 

 vark (Orycteropus) and the wart-hog (Phacochcerus) . The larvae belong 

 to the genus C/mromyia, and they behave like those of Auchmeromyia. 

 3. There are haemophagous larvae on birds. Thus in 1844 "Dufour 

 found that young swallows had their blood sucked by the larva of a 

 Calliphorid fly (Phormia sordida Zett. = Ph. azurea Meig.), and this 

 has recently been confirmed by H. du Buysson. The sucker of the 

 larva, figured by Roubaud, is furnished with a marginal collar of 

 radially arranged processes, spine-like, but not very rigid. These larvae 

 do not show the erection characteristic of those previously mentioned, 

 but lie flat. Roubaud observed their suction on naked parts of the 

 skin of guinea-pig and fowl, and on man. Rodhain has recently 

 observed another haemophagous larva in the Belgian Congo. It 

 occurred in the nest of Passer griseus, and was seen to be able to 

 nourish itself on a fowl. 



All the cases known show (1) adhesion by means of the margin of 

 the first post-cephalic segment, which acts like a sucker, (2) scarification 

 by buccal hooks, and (3) suction by the pumping movements of the 

 invaginated pseudo-cephalon. Two conditions must be fulfilled : the 

 skin of the host must be naked, and the host must be at rest. The 

 larvae cannot move far. The parasitism of Auchmeromyia is not 

 known among nomads. The temporary parasitism is a step towards 

 permanent cuticolous parasitism, the " ver des cases " pointing on to 

 the " ver du Cayor," and the Phormia sordida to species of Mydsea on 

 South American woodpeckers. 



Myiasis and allied Diseases.f— E. Roubaud has given an account 

 of the parasites causing myiasis and similar diseases in man and his 

 stock in West Africa. He deals, for instance, with the blood-sucking 

 larvae of Auchmeromyia and Ghceromyia, with muscid larvae developing 

 in cutaneous wounds, with deeply penetrating CEstrid larvae, with " Ver 



k* C.R. Soc. Biol. Paris, lxxviii. (1915) pp. 92-7 (2 figs.), 

 t Agents Parasitaires Producteurs de Myiases, etc. Paris : (1914) 252 pp. (4 pis.). 

 See C.R. Soc. Biol. Paris, lxsviii. (1915) pp. 71-2. 



