ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 193 



the following conclusions. In the lees evolved Diptera (Tipulidae, 

 Culicidae) the larval adipose tissue is preserved in the adult stage. In 

 Brachycera and Pupipara the iniaginal adipose tissue is a new forma- 

 tion, derived from mesodermic elements, namely from the larval muscular 

 tissue which has been disrupted. In all cases the adipose tissue is the 

 seat of the deposition of albuminoid substances during the nymph 

 period, derived either from the food ingested at the very end of the 

 larval stage or from the destruction of larval organs. In carnivorous 

 forms the deposition of the albuminoid substance is very late, and does 

 not commence until the larva ceases to feed and begins to dispose itself 

 for transformation into the nymph. In vegetarian forms the deposition 

 is earlier and begins during the maturation of the larva, sooner too in 

 those which eat fresh vegetable stuff than in those which devour rotting 

 food. 



Egg-carrying Habit of Zaitha.* — Florence W. Slater has some 

 interesting notes on the habit that certain bugs of the family Belosto- 

 midse (e.g. Zaitha fluminea and Serphus dilatatus) have of carrying their 

 eggs on the back until they are hatched. Those who have described 

 this habit seem to have taken for granted that it is the female who 

 carries the eggs. But in the case of Zaitha at least it is the male. 

 The eggs are placed, not without much resistance, by the female on the 

 upper side of the wings of the male ; he is unable to fly, and chafes 

 under his burden. Occasionally one was seen brushing the eggs care- 

 fully to free them from foreign particles, but most tried to kick them off. 



Wing- Muscles. | — Dr. L. Petii has made an elaborate study of the 

 musculature of the wings in Diptera and Hymenoptera ; and, by means 

 of a diagrammatic projection of these in three layers, makes it- possible 

 for the reader to get some glimpse of the differences and agreements 

 that obtain between the various types. 



Collembola and Thysanura of Edinburgh District.^ — Messrs. G. 

 H. Carpenter and VV. Evans give a list of four species of Thysanura 

 and fifty-nine of Collembola, and they compare their results with those 

 from Scandinavia, Finland, and around Hamburg. Most of the Edin- 

 burgh species are widely distributed over the Palsearctic region. It 

 is difficult to say exactly how many species have been recognised in the 

 British Isles. Roundly, the number may be stated at about 75 Spring- 

 tails and four Bristle-tails, of which all the latter, but only 63 of the 

 former, have as yet been found in Scotland. 



Is there Parallelism between Old and New World Odonata ? §— 

 Dr. P. P. Calvert notes that when the exclusively American genera 

 Dythemis, Paltothemis, Brechmorhoga, Scapanta, and Macroihemis, are 

 compared with Schizonyx, Pseudomacromia, and ZygonijX, genera confined 

 to the Old World, it is evident that in spite of the resemblance in many 

 peculiarities, no complete parallelisms in structure exist. " We do not 

 yet know enough of the relationships of the Libellulinae to enable one 

 to form an opinion on this question : Have the peculiar forms of the 



* Amer. Nat., xxxiii. (1899) pp. 931-3. 



t Bull. Soc. Eutomol. Ital., xxxi. (1899) pp. 1-45 (3 pis. and diagrams). 

 X Proc. Roy. Phys. Soc. Edinburgh, xiv. (1898-9) published 1900. pp. 221-66 

 (4 pis.). § Proc. Acad. Nat. Sci. Philadelphia, 1899, pp. 245-53. 



