456 ORDER CILIO-FLAGELLATA. 



ones directed forwards in a straight line, one longer than the other, closely 

 approximated at their bases. Length 1-120". 

 HAB. Salt water : Norwegian coast (C. & L.). 



This species most closely approaches C. furca, and is not improbably a variation 

 only of that type ; provisionally, it may be distinguished from that form by the 

 shorter proportions of the horn-like processes, neither of which exceed the length of 

 the body, and by the close proximity of the two anterior ones, which seem to spring 

 from a common base. 



Ceratium fusus, Ehr. sp. PL. XXV. FIG. 40. 



Cuirass elongate-fusiform, armed with two horn-like processes only, each 

 of these about three times the length of the body, and produced in the 

 same plane respectively from the anterior and posterior segments of the 

 cuirass ; the posterior process usually straight, the anterior one slightly 

 curved. Length 1-120" to 1-90". 



HAB. Salt water. Colour yellow ; highly phosphorescent. 



Identical with Ehrenberg's Peridinium fusus. Claparede and Lachmann remark 

 that the customary third horn-like process, though not conspicuously represented, is 

 often present in the form of a short spine or slight protuberance, near the base of 

 the single developed anterior horn. Examples of this species were obtained by the 

 author off Falmouth in July 1879, m connection with the summer excursion of the 

 Birmingham Natural History Society. A distinct ovate endoplast was observed in a 

 crushed, spirit-preserved specimen. 



Ceratium candelabrum, Ehr. sp. 



Contour of cuirass resembling that of Ceratium furca ; body depressed, 

 greatly dilated, its surface areolate and cribrate, the equatorial furrow 

 straight, the anterior border oblique ; the three horn-like processes produced 

 abruptly from the body portion, the basal horn about twice the length of 

 the body, the two anterior ones unequal, neither of them exceeding one-sixth 

 the length of the basal process, their surfaces ornamented with unevenly 

 developed parallel rows of asperities. Total length 1-120". 



HAB. Salt water : Adriatic. Colour yellowish-brown. 



Ceratium lineatum, Ehr. sp. 



Contour of cuirass resembling that of Ceratium furca but of smaller 

 size ; its surface ornamented with punctate longitudinal striae, about twelve 

 such striae being included in the half exposed to view. Total length 1-384". 



HAB. Sea water : Newfoundland. 



Ceratium eugrammum, Ehr. sp. 



Contour somewhat resembling that of C. furca or C. lineatum ; surface of 

 cuirass longitudinally striate, the intervals cribrate, not areolate ; body 

 conical, tapering gradually into the straight, posterior or basal, horn-like 

 process, which equals the body in length ; the two frontal processes of 

 unequal length, both shorter than the body. Total length 1-180". 



HAB. Salt water : Adriatic, with phosphorescent water. 



