70 Chapter IV 



merely some of the more common and better-known representatives 

 of the Invertebrata and dwell for a few moments on the phenomena 

 manifested in their organism, into the midst of which have been 

 introduced a few nucleated red blood corpuscles 1 . 



If a small drop of defibrinated blood from a goose be injected 

 beneath the skin of a snail and another under the skin of a cockchafer 

 larva, the red corpuscles are disseminated in the blood fluid which, of 

 itself, is incapable of modifying them, but at the end of a few hours 

 the leucocytes of the two invertebrates that we have chosen for the 

 experiment will have ingested a certain number of the injected 

 red blood corpuscles. The next day red blood corpuscles are still to 

 be found intact in the blood plasma, but the great majority have been 

 devoured by the leucocytes (Fig. 13). Inside these cells the red 

 corpuscles undergo constant and marked changes. In the snail they 

 become round and their walls permeable. In the vacuoles that are 

 produced around the ingested red corpuscles dissolved haemoglobin 

 is found (Fig. 14) ; a portion of this colouring matter passes into the 

 nucleus of the red corpuscles, so that it also has undergone a pro- 

 found change (Fig. 14). Many of the nuclei become emptied, only 

 the peripheral layer remaining. This layer and the membrane of the 

 red corpuscle are the parts that resist the action of the leucocytes 

 longest and they are found for some time after their ingestion. The 

 white corpuscles of the snail, having devoured one or more red 

 corpuscles, may themselves become the prey of their fellows. 



In the " ver blanc " (French popular name for the larva of the 



cockchafer) the phenomena of resorption of the red corpuscles of the 



goose resemble those just described. The blood plasma leaves intact 



the red corpuscles which undergo no change until they have been 



ingested by the leucocytes. The haemoglobin diffuses into the 



leucocyte, whilst the nucleus and the membrane persist for a very 



[76] considerable period (Fig. 15), 'though they lose their normal aspect, 



shrivel, and become transformed into an irregular mass of brown 



[77] pigment which may remain in the substance of the leucocyte 



(Fig. I5,p) for weeks. 



Having once injected goose's blood into snails and"vers blancs," 

 if we repeat the injection several times, the phenomena observed are 



1 The resorption of the red blood corpuscles by the phagocytes of larvae of 

 starfish (Bipinnarid) and of Phyllirhoe has been described in my paper on intra- 

 cellular digestion in the Invertebrates in Arb. a. d. Zool. Inst. d. Univ. Wien, 1883, 

 Bd. v, Hft 2, 8. 141. 



