1903.] 



NATURAL SCIENCES OF PHILADELPHIA. 



337 



NOSEMA GEOPHILI, sp. n., A MYXOSPORIDIAN PARASITE OF GEOPHILTJS. 



BY HOWARD CRAWLEY. 



On May 21, 1900, a specimen of Geophihis was taken in the Harvard 

 Botanical Garden, at Cambridge, Mass. The intestine of this centi- 

 pede was teazed and crushed upon a slide, fixed in corrosive subUmate 

 and stained with thionin. The preparation showed innumerable 

 individuals of the vegetative stage of a coccidian, probably a species 

 of Eimeria, and some 30-40 specimens of the 

 parasite here figured and described. 



Of these, the smallest, shown in figs. 1 and 

 2, were for the most part nearly oval cells, with 

 occasionally a blunt prolongation at one end. 

 They ranged in length from 30 microns upward. There was no distinc- 

 tion to be made out between ectoplasm and endoplasm, the cell sub- 

 stance being essentially uniform. It stained rather deeply with 

 thionin, was dense in structure 

 and beset with numerous vacuoles. 

 No definite membrane could be 

 made out. 



These smaller bodies were 

 mostly uninucleate, although in 

 some the nucleus had already 

 divided. The nuclei themselves 

 were ellipsoidal bodies, with a 

 faintly staining ground substance 

 and a large and conspicuous karyo- 

 some. The ground substance was 

 doubtless a liquid in the living 

 animals. The karyosomes stained 

 intensely in thionin and were in almost every case vacuolated. 



The larger specimens, shown in figs. 3 and 4, attained a length of 

 1.50-200 microns. Their protoplasm was much less dense than that 

 of the smaller forms, and showed a spongy structure. There was no 

 differentiation into ectoplasm and endoplasm. The nuclei were gen- 

 erally arranged in pairs, indicative of recent division, but the prepara- 

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