THE LEUCOCYTES IN ORGANIC FUNCTIONS. 679 



ments and the excrementitious products, are disposed of must 

 be ascertained. 



In the sponge the materials rejected by the phagocytes 

 "and which collect in the larger efferent canals," says Metchni- 

 koff, are eliminated "through large apertures of crater-like 

 shape, the walls of which, according to some authors, are fur- 

 nished with muscular fibers." What have we in the leucocytes 

 to fulfill this function: i.e., to represent what in the higher 

 forms constitutes the intestinal canal? It seems to us that this 

 is particularly well shown in several of the figures in Gul- 

 land's illustration. In Fig. 10, for instance, a few "fibers" 

 our canaliculi may be seen to project from the inner aspect 

 of the line which to us represents the practically empty side of 

 the vacuole. The same arrangement is clearly to be seen in 

 Figs. 11, 12, 13, and 16.- 



If all the foregoing features are considered collectively, 

 they seem to us to suggest that: 



1. Leucocytes can ingest solid, semisolid, and liquid bodies 

 through their cell-substance in two ways: (1) by projecting pseudo- 

 podia which infold or inglobe them; (2) by absorbing them without 

 projecting pseudopodia. 



2. Solids and semisolids are mainly ingested by infolding, 

 and semisolids and liquids by absorption; but all substances, with 

 what plasma accompanies them, are collected in a vacuole that sur- 

 rounds the nucleus and in which the latter lies free; and, at times, 

 in the smaller vacuoles in the cytoplasm. 



3. What physiologically useful bodies are formed in the cell 

 are mainly elaborated in the nuclear canaliculi and the perinuclear 

 vacuole, and are collected in the form of granules in the canaliculi. 



4. All the functions of the cell are probably governed by the 

 astrophere. 



THE GKANULES AS SECKETOKY PKODUCTS. Gulland refers 

 to granules or microsomes in the following words: "Ehrlich 

 regarded the seven varieties of granules which he described as 

 being all formed by the cells, and as being either reserve mate- 

 rial or products for excretion. Hankin [1892-93] took the view 

 that the acidophile granules were secretory products, contain- 

 ing 'alexins/ and destined to be secreted into the blood or 

 lymph. Kanthack, Hardy, and Keng have taken much the 



