2568 The Zoologist — April, 1871. 



of life warrants my considering it a new species, distinct from all those 

 whose economy is known to me." 



Papers read, dx. 



Dr. Sharp communicated " Notes on some British species of Oxypoda." 

 After remarking upon the extreme state of confusion that existed respecting 

 the species of this genus, Dr. Sharp proceeded to critical notes upon most 

 of the previously recorded British species, and described four as probably 

 new to science, viz., 0. petita, hitherto confused with 0. cunicularia, Er., 

 generally distributed in England and Scotland ; 0. edinensis, from near 

 Edinburgh ; 0. verecunda, from near London and in the feus ; and 

 O. tarda, from salt-marshes near Dumfries. 



Mr. Lowne (who was present as a visitor) read, " Observations on 

 immatui'e sexuality and alternate generation in insects." The author 

 thought that species originated occasionally from the maturity of the sexual 

 organs before the acquirement of the adult characters. He had been 

 induced to believe that such is the case, from the early j)eriod at which the 

 sexual organs first make their appearance in the embryo and larva, from the 

 fact that some larvae have been taken in copula, and from an analogous 

 phoenomenon which had been observed among the Echinodermata. In the 

 course^ of the paper he had occasion to enter largely into details of correlation 

 of development between the cutaneous and sexual organs in insects. He 

 stated his belief that such correlations often gave rise to secondary sexual 

 characters. The paper concluded with a comparison between acquired and 

 direct larval forms. The author thought the larva and pupa of insects were 

 probably all acquired, and not direct, stages of development. 



With reference to Mr. Lownes remarks on the early development of the 

 sexual organs in insects, and with a view of disproving a not uncommon 

 idea that the sex is determined by the supply of food (or its quality) 

 furnished to the larva, Mr. Briggs detailed some experiments he had 

 made. A number of larvae of Liparis dispar were separated into two 

 divisions, about sixty in each. One lot were fed upon hawthorn ; the other 

 upon elm. In the elm-fed larvre the imagos produced were about equal as to 

 eex, but there were only two perfect females ; the males of the ordinaiy size. 

 In those fed upon whitethorn, the sexes were again about equal in number, 

 but tbe males were much smaller and paler, whereas the females were much 

 finer, and scarcely any of them imperfect. Again, with a view of determining 

 whether any truth e.xists in the statements of old authors that larvae differ 

 in colour according to sex, Mr. Briggs experimented upon two forms of the 

 larva of Tricliiura cratsegi ; one form being ringed, somewhat like the lai-s^a 

 of Bombyx rubi ; the other mottled. These forms were figured by Hiibner 

 as of different sexes ; but the first-named seemed to be dying out, and was 

 described by none of the more I'ecent writers. From a batch of eggs, Mr. 



