178 I. IJIMA : HEXACTINELLIDA. I. 



In view of the usually well preserved state in which we 

 meet with the thesocytal spherules in sections of Acantliascus 

 cactus, Rhahilocalyftus capillatas, &c., before raeutioned, 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 splierules 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, eosiu, htematoxylin, 

 (&c. 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 ('99a, p. 207) stated : 

 ' Wahrscheinlich handelt es sich um tin Stoffwechselprodukt, 

 ahnlich dem Glycogen, vielleicht auch um eine dem Amylum 

 oder dem Fett vergleichbare Eeservenahrung. Doch mcichte 

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

 chemischen Reactionen weder Glycogen noch Am^'lum noch Fett 

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

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

 ('88, p. XL). 



*A proiiiMinred ca'ie of the inconstant heluivior of tlicsocytal splierules toward stains is 

 offered by Amnthmni^t cadua. Colored with acid-fnchsin after hardening, all the spherules 

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

 not at all or but faintly stained. Jlethyl-blne gives similar results. Combination-staining 

 with the two kinds of stains just mtntioned, or with ha?matein-alum followed by either 

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

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

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

 at difTerent stages of their existence. 



