312 A. TERAO : 



exactly the same microchemical properties as the detrital fragments found 

 in or about the photophores. They float in the blood. Examination of 

 the branchial glands showed no indication of their activity in excreting the 

 granules." Remarkable is the fact that, whenever there was the presence 

 of the granules in the gill-blood, this stained more or less yellowish by 

 Freeborn's picro-nigrosin, instead of bluish as it usually does. Greater the 

 quantity of the granules present, the stronger is the yellowish tinge acquired 

 by the gill-blood. In some of the liver cells I have also not unfrequently 

 found similar or identical granules, each inclosed in a relatively large vacuole 

 in the cell-body. They were probably destined to be thrown out into the 

 digestive canal. Further, masses of apparently the same nature as the 

 granules in question were discovered in the cavities of the antennal 

 glands. 



4) The basement membrane. — This is a thin but distinct 

 membrane at the base of the photogenous layer (fig. 1, bnì). A limited 

 number of flattened nuclei is distinctly present in it. As before mentioned, 

 the substance of the membrane is directly continuous with that of the 

 connective strands. Peripherally and beyond the margin of the photogenous 

 layer the membrane thins out and becomes ill distinguishable as such. I 

 should think that the membrane and the connective strands are, alike the 

 photogenous cells, derivatives of the lens epithelium or the hypodermis, 

 and that the two together may be regarded to form a single structure which 

 gives support to the photogenous cells, somewhat as the neuroglia does to 

 ganglion cells. 



The layer which Kemp has called the second cellular layer in the 

 photophore of 6". challcngcri (1. c, p. 642), is undoubtedly identical with 

 the membrane under consideration. A similar or the same membrane 

 seems to exist also in the photophore of Acanthcphyra deb ili s , judging 

 from the microphotograph given by the same author (pl. LIII, fig. 2), 



1) Cuénot, L., 1855. Etudes physiologiques sur les Crustacés décapodes. Arch. Biol., tome 

 XIII. 



