320 SUMMARY OF CURRENT RESEARCHES RELATING TO 



' Study of Setal Pattern of Caterpillars and Pupae. — A. Schierbeek 

 {Tijdsckr. Nederlancl Dierk. Ver., 1917, 15, 261-418, 5 pis.). A wide 

 study of caterpillars and pup^ has led the author to the following con- 

 clusions : — The modern architecture of the insect's thorax is quite 

 secondary. The anal segments vary considerably in number in different 

 species. To begin with all the abdominal segments bore a pair of legs. 

 The various types of setal arrangement, for which a new nomenclature 

 is proposed, can be derived from each other. A metamerically repeated 

 pattern of pigment spots is more primitive than a pattern of stripes. The 

 change of setae into verrucsB is a reversible process. The pupa and the 

 first caterpillar instar are both primitive, while the other larval instars 

 are to be considered as secondary adaptations. The pupa is to be regarded 

 as a sub-imaginal stage which has become secondarily stationary. The 

 various types of caterpillars have for the most part evolved independently 

 of or parallel to one another. A general larval pattern for the Holome- 

 tabola is still uncertain. J. A. T. 



Bacterial Disease of Larvae of June Beetle.— Z. Xorthrup {Rep. 

 Michigan Acad. Sci., 191 o, 15, G-l). The grubs of the June beetle 

 {Lachnosterna sp.), which do serious damage to crops, were found 

 infected by a Micrococcus which blackened the tissues. Healthy larvae 

 placed in inoculated soil were quickly infected, especially if a cut was 

 made in the integument. The disease was transmitted to Allorhina 

 nitida, another June beetle, and to the cockroach. It may turn out to be 

 useful as a remedial measure. Rabbits and guinea-pigs are immune. 



J. A. T. 



Muscid Larva sucking Blood of Nestlings. — 0. E. Plath {Publi- 

 cations Univ. California, Zoology, 1919, 19, 191-200). Evidence of 

 nestling birds {Astragalinus, Zonotrichia, etc.) being sucked and weakened 

 or killed by larvse of Frotoccdliphora azurea (Fallen). The larva3 were 

 gorged with blood, which is stored in a diverticulum of the oesophagus 

 just behind the pharynx. Pupation occurs in the faeces at the bottom 

 of the nest. Some blood seems to be necessary if the larvae are to reach 

 maturity. Forty-four nests infested with larvae of P. azurea (and 

 P. chrysorrho^a) have been recorded. J. A. T. 



Chromosomes in Larva of Corethra plumicornis. — Armand 

 Dehorne {Arch. Zool. Exper., 1919, 58, Notes et Revue, pp. 25-30, 

 10 figs.). The somatic cells show three chromosomes, which seems to be 

 the diploid number. The smallness of the number is remarkable, and 

 the fact that it is an odd number. How the meiotic division is accom- 

 plished lias not been observed as yet. The material is well suited for 

 the study of mitosis. J. A. T. 



Larva of Micrometrus lineatus. — F. C. Eraser {Records Indian 

 Museum, 1919, 16, 197-S, 1 pi.). This dragon-fly larva from Poona 

 lives in quickly running water, holding on tightly to roots, submerged 

 twigs and the like. They are difficult to collect because they grip 



