138 SUMMARY OF CURRENT RESEARCHES RELATING TO 



been badly wounded in the abdomen. There is a sort of thoracic cycle. 

 In the convolvuhis moth there is also a small metatergal pulsatile 

 organ, which receives alary veins. But no connexion with aorta or 

 dorsal blood-vessel c'buld be seen. In Dyticidse it is this metatergal 

 pulsatile organ that is of the greater importance. J. A. T. 



Intestinal Epithelium of Silkworm, — A. FoA {Boll, Lah. Zool. 

 Agric. Fortici, 1918, 12, 217-44). The mid-gut epithelium shows 

 cylindrical and calyciform cells, differing in structure and function. 

 Both are secretory, but the cylindrical cells are likewise absorbent. In 

 diseased (flaccid) silkworms the calyciform cells are reduced or modified. 



J. A. T. 



Male Genital Tube in Coleoptera. — Frederick Muir (Tratis. 

 Entomol. Soc. London, 1918, 22, 3-9, 1 pi.). This organ arises as a 

 tube in a median position from the connecting membrane between the 

 ninth and tenth sternites. There is no evidence whatever to indicate 

 that it is composed of amalgamated paired organs (called parameres by 

 some authors) ; the terminal lobes, cap-piece and tegminal strut are 

 secondary outgrowths from the tegminal fold. There is no indication 

 that any abdominal segment or sternite is incorporated into the tube. 

 The organ is a tubular evagination and no more. J. A. T. 



Spiracles of Some Muscid LarvsB. — John L. Froggatt {Proc. 

 Linn. Soc N.S. Wales, 1918, 43, 658-67, 1 pL). An account is given 

 of the minute structure of the spiracles of four species of CalUphora, 

 Lucilia sericata, and Ophyra nigra. This has a practical interest, for it 

 is found that from the posterior spiracles in particular it is possible to 

 identify the different species, even when they are rotten. The spiracles 

 are probably very important in connexion with the destruction of the 

 maggots of these species by poison, for apart from the mouth and anus 

 they are the only openings. In these species there are no pores in the 

 cuticle as there often are in insect larvae. But the important point 

 zoologically is the specificity of the spiracular apparatus. J. A. T. 



Bot-Flies. — S. Hadwen and A. E. Cameron {Bull. Entomol. 

 Research, 1918, 9, 91-106, 1 pi., 10 figs.). Careful descriptions and 

 admirable figures are given of three species of Gastrophilus occurring in 

 Canada — G. intestinalis, G. nasalis, and G. hsemorrhoidalis. They 

 differ in the mode of attachment of the egg to the hair, in the external 

 features of the newly hatched larvae, and in the appearance and habits 

 of the adults. The eggs ot'G. intestinalis do not readily hatch unaided, 

 but apparently require the application of moisture and friction or shock. 

 A large number of the eggs of G. nasalis hatched spontaneously, and so 

 did a few of those of G. Iiseniorrhoidalis. This supports the view that 

 the larvEe of these two species may penetrate directly into the integument 

 of the host. The lesions on the skin of the intermaxilloxy space and the 

 lips observed at the time the eggs were hatching may be due to direct 

 penetration of the larvas of G. nasalis and G. hsemorrhoidalis respectively. 

 The newly emerged larvae of G. intestinalis failed to penetrate the hair- 

 bearing skin of the horse, but positive results were obtained when they 



