264 SUMMARY OF currp:nt researches relating to 



Arthropoda. 

 a. Insecta. 



Wing-design of Mimetic Butterflies. — J. F. van Bemmelen 

 {Proc. K. ATcad. Wetenschappen Amsterdam, 1920, 23, 877-86). The 

 interesting suggestion is made that the pattern of mimetic forms belongs 

 to a stock of features characteristic of the genus, the family, or the 

 order. In some cases, and to some degree, mimicry may be explained 

 by supposing the resemblance between two or more non-related forms 

 to have started at an early period, when the ancestral types of different 

 butterfly-families looked more hke each other than nowadays, on account 

 of the primitive colour-pattern common to them all. This view is in 

 line with Haase's suggestion : " The mimetic transformation was 

 preceded in most cases by atavistic phenomena from the side of the 

 females, which in the beginning reached back to the patterns of the 

 nearest relatives, but as the process proceeded, passed over to those of 

 more distant forerunners, and in this way procured the material for the 

 mimetic adaptation." J. A. T. 



Fat-cells of Insects during Metamorphosis.— Charles Perez 

 {Arch. Zool. Exper., 1920, 59, Notes et Revue, 1, 5-10). During the 

 metamorphosis there is no evacuation of urates nor extraction of them 

 by the Malpighian tubules from the l)lood. At the end, however, when 

 the Malpighian tubules begin again to function there is " une veritable 

 debacle unique," which results in the rectum being fllled with a sort of 

 meconium which the imago gets rid of immediately after hatching. 

 Now the appearance of urates in the lumen of the Malpighian tubes, 

 coinciding with the disappearance of the urates in the fat-cells (pseudo- 

 nuclei of the albuminoid inclusions), suggests that the urates pass from 

 the fat-cells to the blood and thence to the tubules. The cells in question 

 may be regarded as "accumulating kidneys." J. A. T. 



Poplar Longhorn. — AValter Ritchie {Annals Applied Biology, 

 1920, 7, 299-343, 3 pis., 25 figs.). An account of the structure and 

 habits of Saperda carcharias, the Large Poplar Longhorn beetle, whose 

 larvte bore in the stems of poplars. There is considerable difference 

 between the sexes, e.g. in size, colour and tarsal claws. The eggs are 

 laid in the bast or the outer wood, and they resemble closely the 

 surrounding tissues. The larva is a soft, fleshy, legless grub ; the 

 shiny-white pupa becomes gradually dark grey. A description is given 

 of the reproductive organs of both sexes. After emerging from the 

 tree the adult beetles feed on the leaves, biting on the surface, never at 

 the margin. The males fly from tree to tree. In both sexes there is 

 stridulation produced by rubbing the hind margin of the pronotum 

 upon the central anterior portion of the prolonged mesonotum. Mating 

 occurs on the twigs and branches. The female selects the site for 

 oviposition with some care. The egg-bites, when newly cut, are very 

 narrow thin lines ; they gape afterwards into dark cracks. The 



