20 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



17. One macronuclear mass in 17. From one to six such masses, 

 division. each of which divides. 



18. None described. 18. A very definite and constant 



body below the attachment disc, 

 which is probably a micronucleus. 



19. Entoplasm of oral disc struct- 19. Entoplasm of whole body 

 ureless, slimy, and somewhat gran- distinctly alveolar and granular, 

 ular. That of neck and attachment 



disc alveolar. 



Many details of the structure of Licnofhora require fur- 

 ther study, and the phenomena of conjugation are above all 

 of the greatest interest. It is hoped that a future opportun- 

 ity for work upon this organism will lead to the clearing up 

 of these points, which for the present, however, must be 

 offered in an incomplete form. 



To the great courtesy of Privat Docent Dr. H. Wallen- 

 gren of the University of Lund, Sweden, I owe especial 

 thanks for sending me slides of L. auerbachiiiox comparison 

 with the Monterey species, 



Boveria, gen. nov. 



With Licno^hora macfarlandi , in the respiratory tree of 

 Holothiiria calif ornica, occurs a second ciliate infusorian 

 of smaller size and heterotrichous structure. This form 

 differs so widely from any previously described that I pro- 

 pose for its reception the new genus Boveria with the fol- 

 lowing characters. 



Animal heterotrichous, cylindrical or tapering, with rounded ends; cilia 01 

 two sorts, (i) a general body system of fine cilia arranged in slightly curved 

 longitudinal rows, (2) a terminal peristomal spiral of long coarse cilia in a 

 double row, closed at both ends, and opening out at the inner end to enclose 

 the terminal mouth. Macronucleus oval, central; micronucleus nearer aboral 

 end. Contractile vacuole near oral end. Reproduction by oblique fission. 



Genus dedicated to Dr. Theodor Boveri, Professor of 

 Zoology in the University of Wiirzburg. 



Boveria subcylindrica, sp. nov. 



Plates IV and V; Plate VI, Figs. 83 and 84. 



General Description. — In the living respiratory tree 

 Boveria is generally seen attached to the membrane by its 

 ciliated base and extending straight out into the lumen. In 



