282 Royal Suciefi/. 



blood of insects and of the Vertebrata, to trace the changes which 

 the former undergo as compared with those of the latter, and to 

 show that in development and function they are analogous to secre- 

 ting cells. 



In pursuance of this object, he premises a brief notice of what 

 little was already known respecting the corpuscle in the Articulata, 

 and of the different descriptions given of it by Cams, Spence, Wag- 

 ner, Bowerbank, Edwards, Baly and some later observers, all of 

 whom have described it differently, one only, Mr. Bowerbank, ha- 

 ving correctly indicated Its form. 



He then proceeds to state, that while engaged on other observa- 

 tions in June last, he found that the oat-shai)ed corpuscles which are 

 so abundant in the caterpillar state of the insect, almost entirely dis- 

 appear before the insect has arrived at the perfect, or butterfly state, 

 in which, a few days after the insect is fully developed, scarcely a 

 isingle oat-shaped corpuscle is to be found ; but that in the place of 

 these, there are numerous very minute rounded bodies, spherules, 

 and also many flattened, obtusely oval or barrel-shaped, double con- 

 cave discs. Both these forms of corpuscle have molecular move- 

 ments, which are most energetic in the spherules. 



He next makes some general observations on the composition of 

 the blood of the Invertebrata, and questions the accuracy of Profes- 

 sor Wagner's view in regarding the blood of these animals as analo- 

 gous only to the chyle of the Vertebrata, at the same time stating 

 his belief that it is not only analogous to true blood, but that it un- 

 dergoes a continued succession of changes through the agency of 

 the corpuscles. These minute bodies first derive nourishment, and 

 the means of growth and increase from the fluid portion of the blood, 

 and afterwards, when they have become fully developed, undergo 

 dissolution, and help to supply the waste of the fluid that has been 

 expended on the nourishment of the different structures, leaving 

 other little bodies, which also undergo development, to assist in the 

 further elaboration of this fluid. He states also, that the develop- 

 ment of these latter bodies appears to have a certain relation to the 

 type of each particular class of animals ; and remarks that in the 

 Vertebrata the size of the corpuscle is perhaps in a ratio inverse to 

 that of the activity and extent of the function of respiration. 



The author states that he has been led to these views, which ap- 

 pear to him to apply to animals generally, by an examination of the 

 corpuscles, and by watching the changes which take place in the 

 blood in lepidopterous insects, and he points out their accordance 

 with those of Wagner, Henle, and Wharton Jones, with regard to 

 the function of the corpuscles ; but proposes to give the details on 

 which his own view respecting the size of the corpuscle is founded 

 on a future occasion. 



He th^n enters more particularly on the consideration of the forms 

 of corpuscle in the blood in the Articulata, which he marks as four ; 

 although, he observes, these are in reality only so many stages of 

 development of one ultimate structure. These forms are,—Jirst, the 

 molecules, which he regards as comparable to the molecules observed 



