THE OPALINID CILIATE IXFUSOEIA]^S. 



91 



This species resembles Z. couchii^ especial!}- the broader individ- 

 uals of the latter species, but has relatively much larger nuclei and 

 must apparently be regarded as distinct. 



Specimens of Opalina ohlanceolata also are present in this same 

 infection. 



Fig. 58. — Zelleriella atelopyxena, X 460 diameteks : a, b, c, e, f, daughter cells ; 



d, g, h, INDIVIDUALS OF THE USUAL SORT; j, AN INDIVIDUAL APPARENTLY IN LONGI- 

 TUDINAL FISSION, THOUGH ITS NUCLEI ARE NOT AS FAR ADVANCED AS USUAL AT THE 

 TIME OF FISSION. 



ZELLERIELLA ATELOPYXENA.^s new species. 



Type. — United States National Museum Cat. No. 16465. 



Host. — Atelopus varius Stannius, two rather scant infections, from 

 United States National Museum specimens No. 30643 (the type in- 

 fection) and No. 30645, both from Pico Blanco, Costa Rica ; W. M. 

 Gabb, collector. 



— From the Greek 6 iivos , a male guest, or n ^ifri, a female guest. 



