392 



in our own country besides himself have given any attention. He 

 has carefully described all the species met with in his own neigh- 

 bourhood in Kent, he has " watched them in their native haunts," 

 noted their habits, " kept them for some time in confinement," 

 experimented upon them in order to ascertain their power of 

 reproducing lost parts, and even worked out all the details of their 

 inmost anatomy', small though they be, and insignificant as they 

 would appear to an ordinary observer.* 



In other papers he has traced the whole process of development 

 in a small species of May-fly, Chloeon dimidiatiim, from birth to 

 maturity, showing that the larva, which is aquatic, passes through 

 no less than twenty changes of form before emerging from the 

 water to assume the winged state, all of which he has described 

 and illustrated by figures, f These numerous changes, which tend 

 very much to modify our old views respecting the metamorphosis 

 of insects, which was generally thought to be confined to the three 

 well-marked stages of larva, pupa, and imago, he considers as 

 having no exclusive relation to the form ultimately assumed, but 

 " bearing reference only to the existing wants" of the insect, and 

 brought about " through the influence of external conditions.'' 

 And the remarks he makes upon this point, in connection with 

 others relating to the general question — What are the circum- 

 stances and conditions which necessitate the striking metamorphoses 

 which most insects pass through 1 more especially, what calls for 

 that death-like repose of the pupa, sometimes extending over many 

 months, before the imago appears, with structure and habits so 

 entirely opposite to what it had in the larva state ? — take us at once 

 to the subject of Darwin's views, whether we accept natural 

 selection, or any other agency, as a right explanation of the 

 matter.! 



* Linn. Trans., vols, xxiii., pp. 429, 589 ; and xxvi., p. 295 ; and xxvii., 

 p. 277. 



t It has been assorted " that tlie pupae of Hymenoptera go through a 

 series of mutations of form, analogous to those of Chloeon, as detailed by Sir 

 J. Lubbock," and Prof. "Westwood has " suggested that the hive bee aflfords a 

 good subject for observations in corroboration of this theory." See £nt. 

 Trans., 3rd Ser., vol. v., Proceed., p. xxiii, 



X Linn. Trans., vols, xxiv., p. 61 ; and xxv., p. 477. 



