146 PHYSIOLOGY OF THE INVERTEBRATA. 



The Ohromatology of the Blood of the Invertebrata. 



We have already alluded to some of the colouring matters 

 contained in the blood of the Invertebrata, but as a consider- 

 able amount of work has been done in this direction, we 

 propose to describe more fully the results obtained in this 

 important subject. 



In England the two great authorities on the colouring 

 matter of.the Invertebrate blood are Dr. C. A. MacMunn, 

 and Mr. E. B. Poulton, P.E,S. Both of these scientists have 

 presented us with a valuable series of investigations which 

 we now proceed to describe. 



The colour of the blood in the Irvoertebrata " does not as a 

 rule belong to the corpuscles, but to what in them answers to 

 the liquor sanguinis of Vertebrates, although there are many 

 exceptions. In some haemoglobin occurs. Thus, Prof. 

 Lankester has shown* that in Glycera, Capitella, and Phororm, 

 and in Solen legumen, it is found in special corpuscles ; while in 

 the vascular fluid of others it is found dissolved, e.g., with cer- 

 tain exceptions in some chsetopod Annelids, in some Leeches 

 {Nejphelis, Hirudo), in Folia sanguirubra (a Turbellarian), in 

 the special vascular system of a marine parasitic Crustacean 

 observed by E. van Beneden, in the general blood-system of 

 the larva of the Midge {Ghironomibs), in the general blood- 

 system of the Mollusc Flanorbis, and in the general blood- 

 system of the Crustaceans, Daphnia and Oheirocephalvs." 



Haemoglobin is also present in the blood of lAtmhricus 

 Arenicola, and Eunice ; and it has already been stated that 

 this haemoglobin is spectroscopically the same as that found 

 in Vertebrate blood. 



The blood obtained from five hundred earth-worms {Limr 

 bricus terrestris) was treated with benzene, which readily 

 dissolves the colouring matter. The mixture was allowed to 

 stand for twenty-four hours at o° C; when it separated 

 into two distinct layers. The one containing the colouring 

 * Proeeedinga of Soyal Society, vol. 21, p. 71. 



