306 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Assimilation of Carbon Dioxide by Pupae.*— Marie von Linden 

 brings forward fresh evidence in support of her conclusion that pupae, 

 e.g. of Hylophila prasinana, are able to assimilate carbon dioxide from 

 the air. 



Malpighian Tubes in Larval Lepidoptera.f— L. Bordas finds that 

 the number of these in caterpillars is six, except in Carpocapsa pomonella, 

 where there are four. They are usually varicose. Their wall consists of 

 an external peritoneal membrane, a basilar membrane, and a secretory 

 epithelium. The urinary reservoir has almost the same structure. The 

 tubes contain crystals of uric acid, urates of sodium and ammonium, 

 oxalate of lime, and, especially, crystalline concretions of carbonate of 

 lime. 



Histology of Metamorphosis.?— Ch. Perez distinguishes three general 

 processes. 1 . There is total atrophy and destruction of the most highly 

 specialised organs of the larva. Except in tbe case of the epithelium of 

 the mid-gut, which is exuviated, the mechanism of the atrophy is by 

 phagocytosis. 2. The most highly specialised organs of the imago are 

 constructed denovo from special embryonic histoblasts. 3. Some struc- 

 tures are gradually altered in situ, passing over from larva to imago after 

 modification. There is a " de-differentiation " and a " re-differentiation," 

 sometimes associated with a curious cellular purgation. In Muscids 

 there is an almost complete destruction and re-construction, but in many 

 other types there is more of the third mode of transformation. 



Metamorphosis of Malpighian Tubes in Muscids. § — Ch. Perez 

 finds that the four Malpighian tubes of the Muscid larvae persist to form 

 those of the adult, whereas in some other cases, e.g. ants, they disappear 

 and are formed de novo. But it is interesting to observe that during the 

 pupa period the Malpighian tubes exhibit a progressive loss of their larval 

 differentiation. They cease for a period to be excretory, and are stores 

 of fatty material. Gradually re-differentiation sets in. 



Living Species of Diplonema.|| — Nelson Annandale gives a diagnosis 

 of a surviving species of this genus of Psychodid Diptera. Three speci- 

 mens were captured in the Darjeeling district (altitude 5000 ft.). The 

 genus Biplonema appears to have been known hitherto from three Tertiary 

 species, which occur in Baltic amber, and from one quaternary form in 

 fossil copal. 



Empididse.^T— M. Bezzi reports on a rich collection of these Dipterous 

 insects made by W. Schnuse in South America, describing no fewer than 

 ninety species. Many of these are new, and six new genera are estab- 

 lished. 



Alimentary Tract and Habits of Simulium columbacensis.** 

 Jivoin Georgevitch discusses this " Goloubatz " fly, which destroys nu- 

 merous pigs, horses, and cattle in Servia. There is a suctorial pump 



* SB. Nat. Ver. Preuss. Rheinlande, 1909, pp. 25-30. 

 t Comptes Rendus, cl. (1910) pp. 737-9. 



% C.R. Soc. Biol. Paris, lxviii. (1910) pp. 167-8. § Tom. cit., pp. 42-3. 



II Journ. Proc. Asiatic Soc. Bengal, -iv. (1908, received 1910) pp. 353-4. 

 % Abhandl. k. Leopold. Carol. Akad. Nat., xci. (1909) pp. 293-408 (1 pi.). 

 ** C.R. Soc. Biol. Paris, lxvii. (1909) pp. 540-2 (1 fig.). 



