34 The Scottish Naturalist, 



" The other question, if the unimpregnated eggs are regularly 

 developed, was answered in the affirmative by repeated experi- 

 ments, which are very simple and very easy to be repeated. I 

 put female wasps, raised by myself, which had not been with a 

 male, on shoots of rose put in a jar in water. As soon as the 

 wasps began oviposition the shoot was placed in a breeding 

 cabinet. After oviposition had ended, the wasp was examined 

 anatomically, and the vesicula seminalis found to be empty. 

 The eggs were examined after 12 hours, and the peripherical 

 layer of cells around the dark yolk was seen ; in the following 

 days the development advanced in the regular manner. 



" Dr Adler gives on five jDages more the most interesting de- 

 tails upon the formation and growth of the gall. As Ji'h. rosce 

 is common here, this part of the memoir is of great value for 

 American students. If we look in Mr P. Cameron's paper, we 

 find about this matter on p. 156, as follows : — 



" ' With the bisexual Cynipidae the males are in some species 

 nearly as common as the other sex; in others, as in Rhodites, 

 they are very rare.' That is all ! 



" On the alternation of generations in Cynipidae the first part 

 of Dr Adler's memoir contains only (6 p.) the beginning of the 

 experiments with Neiwoterus fumipennis. The second part (24 

 p.) was published three months later than Mr Cameron's paper, 

 which contains, nevertheless, some of the names of the species 

 (5 out of 7) treated in the second part, probably out of a pro- 

 visionally published notice, unknown to me. 



**' Dr Adler having raised in 1874 out of all Nacrotenis finni- 

 pennis galls nothing but Spathegaster albipes, decided to observe 

 them more exactly. The experiments with Newotents fiimi- 

 pe7inis were made in 1875 i^^ the following manner: — 



" The galls were collected in the autumn before. When the 

 wasps began to appear, they were put on a small oak-tree in a 

 tub in a cool room. When a wasp began oviposition, each twig 

 was enclosed in a glass tube, after the bud had been marked 

 with a thread. There were marked INIarch 14th, 12 buds; 

 March 19th, 10 buds; March 24th, 8 buds; March 26th, 6 

 buds — in all, 3i6 buds. Besides those, other wasps were put on 

 cut oak-twigs placed in damp earth or sand (in which manner 

 the twigs keep well three weeks and longer as good material for 

 observing the eggs), and after oviposition was observed, the iso- 

 lated twig was covered with a glass bell. The wasps were ex- 

 amined after the oviposition, and the receptaculum seminis found 



