34 SUMMARY OF CURRENT RESEARCHES RELATING TO 



heat of dried pupse, living pupae, pupal fluid, and on the behaviour of 

 pupal fluids under heat and cold. His experiments relate especially to- 

 Deilephila euphorbia and Saturnia spini. 



Innervation of Metacephalic Segment.* — K. W. Verhoeff describes 

 in detail the nerves of this segment, which corresponds to the maxillipede- 

 segment of Chilopoda, and is otherwise known as the microthorax or 

 " Nacken-segment " in insects. As the result of his researches, he pro- 

 poses the new order Oothecaria (including Blattodea and Mantodea), 

 which, along with the Phasmodea and the Saltatoria make up the old 

 order Orthoptera. 



Excretory Processes in Insects.j — Nils Holmgren finds in Apion 

 Jlavipes, one of the Curculionidas, four long Malpighian vessels and two 

 short acinous glands, which are modified Malpighian vessels. In Dacytus 

 niger, one of the Cantharidse, there are six normal Malpighian tubes, 

 but the female has also 6 club-shaped accessory structures, which may be 

 modified Malpighian tubes. 



In both cases the excretory products arise in the nuclei of the ex- 

 cretory cells, pass into the cytoplasm, and are eliminated into the lumen 

 of the organ. The same process was observed after injection with 

 pigments such as methylen-blue. 



Mouth-parts of Insects.J — V. L. Kellogg notes that the determina- 

 tion of the homologies of the mouth-parts is as yet far from satisfactory, 

 especially as regards Diptera. There is need for the solid grounding of 

 interpretation on a more complete knowledge of the development. His 

 paper is a contribution towards this end. 



Stridulation of Death's Head Moth.§ — Ruggero Cobelli has made 

 some experiments with Acherontia atropos, and finds secure evidence that 

 the stridulation is exclusively due to the rhythmic friction of the two 

 portions of the proboscis, one upon the other. It seems necessary to 

 reject the interpretation of the so-called " voice," which has been given 

 by various entomologists from Duges onwards. Of "voice," in the 

 strict sense, there is no evidence ; according to Cobelli the sound pro- 

 duced is wholly due to stridulation. 



Butterflies of Borderland between North and South America.|| — 

 F. D. Godman and the late Osbert Salvin have enriched zoology by the 

 two volumes here referred to on the Lepidoptera Rhopalocera of Central 

 America. Part of the interest of the work is in its analysis of the results 

 of the meeting of the two contrasted faunas of the Holarctic and 

 Neotropical regions. Prof. Poulton writes : " The whole of the vast 

 mass of material in these and the great series of companion memoirs is a 

 remarkable testimony to the insight of P. L. Sclater, in drawing the 



* Zool. Anzeig., xxxvi. (1902) pp. 20-31 (9 figs.). 



t Auat. Anzeig., xxii. (1902) pp. 225-39 (12 figs.). 



X Amer. Nat., xxxvi. (1902) pp. 683-706 (26 figs.). 



§ Verb.. Zool.-bot. Ges. Wien, Hi. (1902) pp. 572-4. 



|| *Biologia Centrali-Amerieana. Insecta, Lepidoptera Rhopalocera,' vols. i. 

 and ii. (1879-1901) xlvi., 487, and 782 pp. and 112 pis. See Nature, lxvii. (1902)- 

 pp. 25-7. 



