32 SCHMIDT ON THE COMPARATIVE PHYSIOLOGY 



the microscope exhibited the most beautiful regular forms, 

 although it was difficult to determine to which system they be- : 

 longed ; they dissolved in acids with considerable evolution of ! 

 carbonic acid, and Prof. Wohler drew my attention to their great 

 resemblance to the crystalline form of Gay-Lussite. In fact, 

 judging from the reaction with perchloric acid, they appeared to 

 contain soda, together with excess of lime, but it was certainly 

 neither the first nor second rhombohedron of calcareous spar. 



The first-mentioned coagulum reacted towards alkalies, by 

 which it was dissolved, and towards nitric acid, which coloured 

 it yellow, as an albuminate. The same appHes to the organic 

 matter of the dried residue, which, by forming pellicles on eva- 

 poration, and becoming but slightly turbid when first heated, 

 appears to be related to caseine. 



If we sum up v\'hat has been stated, it is evident that this blood 

 contained essentially a compound of albumen with lime — which 

 is decomposed even by the carbonic acid of the air, of the water, 

 or of that produced by the chemico-vital reactions — together 

 with phosphate of lime and soda, which amounted by weight in 

 1 000 parts to— 



Water 991-46 



Fibrine 0*33 



.,, /"Albumen 5 '63 \ in a peculiar state 



LLime 1*89 J of combination. 



Phosphate of soda, sul-^ 



phateoflimeandchlo- r 0*33 

 ride of sodium . . J 



Phosphate of lime . . 0*34 

 This peculiar albuminate of lime, which for greater clearness 

 of consideration we shall call neutral, is thus decomposed by the 

 above-mentioned epithelial cells into free albumen and basic 

 albuminate of lime : the latter is secreted as an amorphous mass 

 next the shell, as such, in an almost unorganized condition, obey- 

 ing the laws of crystallization, to contribute to its increase in 

 thickness ; the former (the free albumen) returns with the phos- 

 phate of lime into the circulation, to serve purely animal func- 

 tions ; either the process of cell-formation of the primitive ova 

 in the ovaries, or of the maternal cells of the seminal animalcules 

 in the glandular system of the testicle. 



We have yet to investigate the Zoophytes ; but we shall first 

 glance at the two transition forms of the Cirripeds and Ascidia, 



