24 



ordinarily resistant to the normal strain of the parasite. It is 

 possible that a peculiarly virulent strain of T. gambiense may have 

 been developed in this manner, but all observations show that further 

 specific enquiries are necessary. 



Keilin (D.). On the Life History and Larval Anatomy of Melinda 

 cognata, Meigen (Diptera, Calliphorinae) parasitic in the Snail, 

 HeliceUa {Heliomancs) virgata, Da Costa, with an Account of 

 the other Diptera living upon Molluscs. — Parasitology, Cambridge, 

 xi, no. 3-4, October 1919, pp. 430-455, 4 plates, 4 figs. 



This paper concludes with observations made by M. E. Seguy, who 

 noticed that the larvae of Musca domestica readily devour snails 

 either living or dead, the attacked molluscs often being covered with 

 a mite, Eurenetes limaceum, Schrank. From 50 molluscs collected 

 in January, 9 yielded larvae of M. domestica ; all stages bred from 

 snails are however smaller than those bred from decomposed organic 

 substances. Seguy records the presence of larvae of CaUiphora 

 ^rythrocepJwla and PJiora giraudi, Egg., in snails, in addition to that 

 of Melinda cognata, Meig., dealt with here. 



ScHWETz (J.), Dix Jours d'Observations sur les Moeurs de la 

 Pangonia zonata et de la Pangonia oldii (Deuxidme Note). — 

 Rev. Zool. Africaine, Brussels, vii, no. 2, 1st October 1919, 

 pp. 92-106. 



Observations made at Kakanu, Belgian Congo, during May 1918, 

 show that the presence of Pangonia zonata is closely related to the 

 distribution of a native plant, Acanthus nwnfanus ; whereas P. oldi, 

 although usually found in the same locality, is more abundant in the 

 forest [R.A.E., B, vii, 80]. Both species are blood-suckers, but will 

 only bite man under special circumstances, their chief food being the 

 nectar of flowers. In the district under consideration the flies appear 

 towards the end of the rainy season, i.e., end of April, and disappear 

 during July. 



The species in question recorded as P. zonata has since been 

 identified as P. {Diatomineura) inornuta, Aust., and that treated 

 as P. oldi, although very similar to it, is probably undescribed. 



Vandenbranden (F.). Observation sur des Larves de Lucilia 

 se developpant dans des Plaies. — Rev. Zool. Africaine, Brussels, 

 vii, no. 2, 1st October 1919, pp. 197-198. 



A species of Lucilia has been observed ovipositing in wounds in 

 rodents. The animal under observation was a rat, Cricetomys 

 gambianus, the front paws of which were attacked. The eggs are 

 deposited near the wound into which the emerging larvae make their 

 way. Eggs were also deposited on the back of the animal. In no 

 case were healthy rats attacked. The duration of the life-cycle of 

 the fly from egg to the emergence of the adult is 21 days. 



