364 REPORT ON ZOOLOGY, MDCCCXLIV. 



pini, when it has already spun its web, and it shrinks up in proportion as 

 the parasite grows. The habits of Tryphon eques and Exenterus margina- 

 torius were similar. 5. Microgaster nemorum, Hart. Here again remark- 

 able changes were observed in the larva. In the first stage, the larva, of 1 

 line in length, has nothing remarkable besides the large vesicle at the hinder 

 end. In the second, it is IV" long ; near the alimentary canal (filled with a 

 parenchymatous mass) a pair of forked silk-vessels are discernible ; the vesicle 

 seems to be set with Little pointed tubercles ; the organs of the mouth are 

 merely indicated by four warts. In the third stage the tracheae are deve- 

 loped ; and in the last, in which the larva bores through the skin of the 

 caterpillar infested, to spin its cocoon outside, the vesicle is gone, the 

 several segments have on the upper and under-side crossrows, at the sides 

 oblique rows, of prickles set upon knots ; the parts of the mouth are very 

 faintly developed, only the upper jaws were found well-formed and horny 

 (see his note). A considerable number of new species are described, which 

 I omit without scruple, as the original work is indispensable in studying the 

 species of this family. Only one new genus must be noticed, Macropalpus 

 (vox hybrida !), founded upon Eubadizon leptoceplialm, Hart., distinguished 

 from that genus by the stout palps* and the narrow crown of the head, and 

 by the former character also from Microdus, wliich it resembles greatly in 

 form. It is a very common parasite of Tortrix buoliaua. [This is evidently 

 identical with Microdus obscurator, Nees (although Ratzeburg expressly 

 refers to the latter in comparison), and has already, as the type of a distinct 

 genus, received two different names. (See Westwood's Mod. Classif. Ins. 

 Synops. 63, g. Orgilus.) 



It is some matter of regret that Ratzeburg had not enjoyed the leisure 

 necessary for an attentive study of the various essays on these tribes which 

 have appeared within the last few years, in particular the comprehensive 

 works of Wesmael and Walker. His remarks on classification evince a 

 quick eye and sound judgment ; but, in default of sufficient intimate ac- 

 quaintance with the labours of his predecessors, the species given as new 

 are not in every instance brought under their proper genus, and many of 

 them, doubtless, may be found described already. The descriptions, though 

 sketched with a masterly hand, are so concise that it may be sometimes dif- 

 ficult to ascertain the precise subjects of his interesting observations, except 

 by a reference to the authentic specimens of his collection (at Neustadt 

 Eberswalde), now the property of the state. It were to be wished that 

 some one of the learned Hymenopterists of Germany would confer on 

 science the benefit of such a collation and critical revision of the whole. 

 It is proper to remark that the suggestions to his professional associates, 



* In the text it is "feet," obviously a misprint. 



