PHAGOCYTOSIS AND CLOTTING IN THE 

 PERIVISCERAL FLUID OF ARBACIA. 



JAMES ERNEST KINDRED, 



BIOLOGICAL DEPARTMENT OF WESTERN RESERVE UNIVERSITY, 

 CLEVELAND, OHIO. 



The perivisceral fluid of the Echinoidea contains certain 

 formed cellular elements which have been observed and described 

 by Valentin ('42), Williams ('56), Hoffman ('72), Prouho ('86), 

 Geddes ('80), Cuenot ('91) and Theel ('96). For most of our 

 knowledge of these cellular elements we are indebted to Geddes 

 and Cuenot. Goodrich ('19) in his discussion of the leucocytes 

 of the invertebrates is the most recent contributor. 



Cuenot observed that these formed elements were found not 

 only in the perivisceral cavity, but also in the lumina of the 

 ambulacral system; in the lacunae of the intestinal walls and in 

 all other organs of the body. He further observed that they 

 were not all of one type, but could be divided into two distinct 

 series, each of which series could be further subdivided. The 

 first series of cells he called "vibratile globules," minute cells 

 6-9 micra in diameter having a head and vibratile tail. The 

 head is mostly nucleus enclosed in a thin sheath of cytoplasm. 

 According to Cuenot the function of this type of cell is to keep 

 the fluid contents of the perivisceral cavity in motion. 



The second series of cells were called "amibocytes" and were 

 subdivided into several different types. The first type, from 

 which Cuenot assumed the other types to be derived, was found 

 abundantly in the lymph-glands. The cells of this type were 

 characterized by a homogeneous cytoplasm, long and numerous 

 pseudopodia, and a relatively large nucleus within which was a 

 distinct nucleolus. Sometimes the amibocytes of this type 

 enclosed yellow or brown refractile granules. According to 

 Geddes these were the most numerous of the corpuscles and all of 

 the investigators have agreed that these cells are the chief agents 

 in the formation of the blood clot. Because of this activity 



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