176 SUMMARY OF CURRENT RESEARCHES RELATING TO 



the tip of testicular and ovarian tubes. It arises from an original germ- 

 cell, and is distinct from a very early date (even in the embryo in Bombyx 

 mori). In the testes it contributes to the nutrition of the germ-cells, 

 acquiring the necessary material partly by dissolution of spermatogonia, 

 partly by assimilating material from the connective-tissue sheath of the 

 testis, and partly by independent secretory production of nutritive sub- 

 stance. After it has done its work, it gradually degenerates. In the 

 ovary the apical cell is practically functionless ; in later stages it 

 degenerates. 



Griinberg also discusses the post-embryonic development of the 

 ovaries in Bombyx mori and Pieris brassiere. He finds that the dif- 

 ferentiation of the germinal elements of the ovary begins daring the 

 larval period. The original oogonia give rise only to ova and nutritive 

 cells. The follicular cells are due to a limited number of epithelial 

 cells of the stalk of the ovarioles, distinctly separated from the germ- 

 cells during the embryonic period. 



Notes on Liparids.* — J. J. Lister refers to the vestigial character 

 of the maxillae in Porthesia auriflua and Psiiura monarcha • they are 

 not accurately opposable to form a proboscis and are shorter than the 

 labial palps. 



Sexual dimorphism is well marked in P. auriflua, secondary sexual 

 characters being found in the " expansion " of the wings, colour, and 

 the larger size of antennas and eyes in the male sex. A paired longi- 

 tudinal groove on the sides of the fourth abdominal segment of the 

 male is probably homologous with the much longer groove found in the 

 males of many Noctuce, notably in Xylophasia poiyodon, extending from 

 the second to the fourth abdominal segment and lodging a remarkable 

 protrusible tuft of hairs. The males of P. auriflua have very keen 

 powers (olfactory ?) of detecting the presence of the female. Death 

 rapidly follows fertilisation. 



The conspicuous satiny-white colouring of the three species Porthesia 

 chrysorrhcea, P. auriflua, and Liparis salicis is contrasted with the quiet 

 buffs, browns, and blacks of the other members of the family, conforming 

 closely with their environment. There is considerable evidence that the 

 conspicuous species are noxious, both in the larval and adult state, by 

 reason of the urticating properties of the hairs. 



Beetles of Ireland.f — W. F. Johnson and J. N. Halbert have pro- 

 duced the first published list of the Irish Coleoptera, including about 

 1C30 species, none peculiar to the country. The authors distinguish 

 three groups : — (a) species which range over central Europe and the 

 Mediterranean region, but are rare or wanting in Scandinavia and 

 northern Europe ; (5) species of northern origin, a good many of 

 which inhabit mountain districts ; (c) species which are found almost 

 exclusively in south-western Europe and the Mediterranean region, the 

 exceptions being littoral species which range as far north as Scandinavia. 

 Most of the Irish representatives of this third group are insects of the 

 sea-shore. The authors think that about forty species in their list have 



* Proc. Cambridge Phil. Soc, xii. (1903) p lfi. 

 t Proc. E. Irish Acad., vi. (1902) pp. 535-827. 



