ZOOL.-VOL. III.] STEVENS— CILIATE INFUSORIA. 3 



I. Licnophora macfarlandi,^ sp. nov. 



Plates I-III; Plate VI, Figs. 68-82. 



Historical Summary. — In 1862, Claus (1862) described 

 a Trichodina-like infusorian, parasitic on the medusa Clad- 

 onema, and in 1865 Meyer and Moebius (1865) found a 

 similar form on yEolis alba, in the Bay of Kiel. That these 

 forms belong to the genus Licnophora is evident from the 

 descriptions and figures, but they have not been identified 

 as to species. 



In 1866, Auerbach discovered and Cohn (1866J described 

 and named Trichodina auerhachii, an infusorian found on 

 Doris muricata at Helgoland. The species was character- 

 ized by an elongated body, by separation of the attachment 

 disc from the oral disc by a narrow neck, and by a left 

 hand peristomal spiral. 



In 1867, Claparede (1867) created the genus Licnophora 

 for a new species, Licnophora cohnii, found on an annelid, 

 Psyrmobranchus protenstis, in the Bay of Naples, and trans- 

 ferred Cohn's Trichodina auerbachii, which he also found 

 on Thysanozoon tubercula, to this genus as Licnophora 

 auerbachii. 



In 1884, Gruber (i884«) named a third species, para- 

 sitic on the dermal branchiae of Asteriscus, in the Gulf of 

 Genoa, Licnophora asterisci. This species Gruber describes 

 as very near to Licnophora auerbachii. 



Fabre-Domergue (1888) regards these three species as 

 identical. He says: "Or, je ne crois pas que I'habitat 

 suffise pour faire separer deux formes parasites qui ne pre- 

 sentent aucune difference d'organisation, et comme j'ai eu 

 I'occasion d'etudier des Licnophora fixees a des Syllis et a 

 des Ophiothrix, et identiquement semblables, je crois que 

 Ton peut, jusqu'a nouvel ordre, reunir sous le premier 

 nom de Licnophora auerbachii, toutes les especes connues." 



Biitschli (1889) mentions Fabre's opinion, but says that 

 there are probably two or three species. 



1 Specific name given out of respect to Dr. F. M. McFarland, Associate Professor of 

 Histology, Leland Stanford Junior University. 





iUM 11! 90, 



