178 I. IJIMA : HEXACTINELLIDA. I. 



In view of the usually well preserved state in which we 

 meet with the thesocytal spherules in sections of Acanthascus 

 cactus, Rhahdocalyptus capillatus, &c., before mentioned, it seems 

 necessary to assume a certain difference in their properties, 

 physical or chemical or perhaps both, at least between those of 

 certain species. After being hardened, the spherules or their 

 residue are shining, strongly refractive and of a yellowish color. 

 Ether or chloroform does not dissolve them away. They now 

 take up intensely such stains as acid-fuchsin, eosin, hfematoxylin, 

 (fee. Borax-carmine colors them only to a moderate degree ; 

 occasionally it leaves them nearly or quite uncolored, the varia- 

 tion being due I think, to certain varying conditions connected 

 with the state of the constituent matter.'^' 



As to the chemical nature and physiological significance of 

 the thesocytal spherules, F. E. Schulze ('gga, p. 207) stated : 

 ' Wahrscheinlich handelt es sich um ein Stoffwechselprodukt, 

 ähnlich dem Glycogen, vielleicht auch um eine dem Amylum 

 oder dem Fett vergleichbare Reservenahrung. Doch möchte 

 ich besonders betonen, dass es nach dem Ausfall meiner mikro- 

 chemischen Reactionen weder Glycogen noch Am)'lum noch Fett 

 sein dürfte.' I completely concur in this opinion. Probably 

 the substance is of an albuminoid nature, as was suggested by Sollas 

 ('88, p. XL). 



*A pronounced case of tlie inconstant belnivior of tliesocjtal spherules toward stains is 

 offered by Acanthascua cactus. Colored with acid-fuchsin after hardening, all the spherules 

 in some thesocytes are intensely stained, wliile those of others in the same preparation are 

 not at all or hut faintly stained. Methyl-blue gives similar results. Combination-staining 

 with the two kinds of stains just mentioned, or with hix-matein-alum followed by eitlier 

 eosin or acid-fuchsin, gives beautiful preparations in which the thesocytes sliow the spherules 

 deeply stained red in some and blue in others. I am inclined to think that this power 

 of selecting different stains is probably due to some inconstancy in the nature of the spherules 

 at different stages of their existence. 



