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coelomic cavity has increased, but not so that in the blood system. 

 To him this is a proof in favor of his conception of the impor- 

 tance of the blood system in resorption, as one can easily 

 understand. I mention it in connection with my own experiments 

 on sea urchins. 



Enriques finds the fat in free form in the coelomic cavity. 

 It is not taken up by the corpuscles, according to him. This 

 agrees very well with my own experiments on sea urchins; 

 there also I did not find any increase in fat in the corpuscles 

 after fat feeding, it disagrees however with the experiments of 

 Chapeaux, mentioned previously. I did not find any free fat 

 in the coelomic cavity of my urchins however. 



21. THE RESORPTION IN ASTEROIDEA. 

 FUNCTION OF THE THEIR „LIVER". 



There is an old question in comparative physiology which 

 Jordan 68) calls the „Leberfrage". The numerous appendages 

 of the middle-gut of invertebrates have usually been called 

 „liver" by the older, especially by the morphological writers. 

 This can not astonish us, since in most groups they are located 

 exactly where the liver is found in higher animals. Furthermore, 

 their secretion frequently contains a yellow or brown pigment 

 and tastes bitter. One of the things which chiefly accounts for this 

 assumption is the fact that they frequently contain glycogen. Their 

 secretion also contains sugar by which even ClaudeBernard 

 6) and 7) was misled. 



Later on it appeared that the secretion of these organs 

 resembled more that of the pancreas of the Vertebrates ; in 

 order to recognize this fact the name „Hepatopankreas (M a x 

 Weber)" was accepted and is used up to the present day in 

 the leading text-books of zoology. 



One of the chief reasons why this belief was not sooner aban- 

 doned is the fact that with the word gut one generally associ- 

 ates the notion of a tube, such as is found in vertebrates. A 

 ramified gut was known to occur in many of the lower groups, e. g. 

 the flatworms and the coelenterates, but the idea that these „livers" 

 are nothing much else but ramified middle-guts, did not at once 

 succeed in getting a foot-hold. Yet, just as in many of these 

 lower groups the respiratory organs branch out all over the 

 body, so to a certain extent, does the digestive tract. In many 

 instances we have to do here with an adaptation to the lack of 

 circulation, the intestine follows the form of the body in order 

 the assure an equal distribution of the food. 



Now in this connection it is very remarkable that organs 

 of the same nature are found in the starfishes, just where the 

 problem of food distribution is most difficult owing to the 

 strange shape of the body. 



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