42 SUMMAKY OF CUIUIENT RESEARCHES RELATING TO 



Antennary Sense-organs of Lepidoptera.* — L. K. Bohm describes 

 those which occur on the surface (sensory " hairs," " bristles," and 

 cones) and those which are sunk in pits, inchiding compound sensory 

 pits. In spite of their variety in detail, all the antennary sensory organs 

 in Lepidoptera show essentially the same structure — a chitinous portion or 

 modified seta, and a nerve ending. 



Alimentary Canal of Lepidoptera.f — Ernst Petersen gives an 

 account of the different types of food-canal found in Lepidoptera. He 

 also describes the minute structure of the various parts. Some of his 

 results corroborate the conclusions of others as to the position of different 

 families in the system. Thus the Hepialidte, which are primitive in their 

 mandibles, venation, nervous system, genital organs, etc., are also primi- 

 tive in their alimentary tract. It is relatively short ; instead of a suc- 

 torial pump there is a crop — i.e., a distal expansion of the oesophagus ; 

 a proventriculus is not more than hinted at ; the mesenteron has no 

 ridges ; the proctodoeum is short and thick ; and so on. From this 

 primitive type the author traces the probable evolution of the gut along 

 various lines. 



Neck-fork of Papilionid Caterpillars. | — Paul Schulze has made a 

 careful study of the " Nackengabel," or protective gland or osmeterium, 

 which is protruded like a couple of snail's horns from the first thoracic 

 tergite. He describes the musculature, the innervation, the gland-cells, 

 the complete histolysis (without almost any phagocytosis) in the pupa. 



After a careful enquiry, he finds that the " Nackengabel " may some- 

 times function as an effective protective organ, but the view that this is 

 its primary significance cannot be upheld. Phylogenetically, the struc- 

 ture may be regarded as a pair of specialized integumentary papillae. 



Food-canal of Caterpillars.!— L. Bordas has made a detailed study 

 of food-canal in general, and of malpighian tubes in particular. He 

 describes the macroscopic and microscopic structure. The malpighian 

 tubes show an external peritoneal membrane, a basilar membrane, a 

 secretory epithelium, a ciliated lining, and contents. The solid contents 

 include crystals of uric acid, urate of soda, carbonate of lime, etc. 

 Bordas emphasizes two points — the origin of the malpighian tubes as 

 diverticula from the posterior intestine, and their renal function. 



Experiments on Pupae. |1 — Peter Kosmiusky has studied the effects 

 "of raising and lowering the temperature. His subjects were pupaj of 

 Vanessa urticae, Gastropacha querclfoUa, 3IaJacosoma neustria, Lymantria 

 dlspar, etc. He describes the changes observed in the imago, —changes 

 in colour and markings, the reduction of scales, the thickening of the 

 chitin on the body, shortening of the wings, shortening of legs, changes 

 in the shape of head, thorax, and palps, reduction of gonads, putting on 

 the characters of the other sex ; and so on. 



* Arbeit. Zool. Inst. Univ. Wieu., xix. (1911) pp. 219-46 (1 pi. and 2 figs.). 



t Jen. Zeitschr. Naturw., xlvii. (1911) pp. lfil-216 (33 figs.). 



X Zool. Jahrb., xxxii. (1911) pp. 181-241 (3 pis. and 27 figs.). 



§ Ann. Sci. Nat. (Zool ) xiv. (1911) pp. 103-273 (3 pis. and 32 figs.). 



11 Zool. Jahrb., xxx. (1911) pp. 321-38 (1 pi. and 6 figs.). 



