1911] Kofoid: The Genus Gomjaulax. 237 



Dimensions : Length, excluding spine, 148 to 167/x ; greatest 

 diameter, 72 to 88/i,; dorso- ventral (oblique), 53 to IQ^; length 

 of antapical, 4 to 18/x; width of furrow, 5 to 8/x. 



•Variation: An exceedingly variable species in size, shape of 

 epitheca, development of surface markings, especially in num- 

 ber and extent of longitudinal striae, width of intercalary bands, 

 and finer surface markings. This added to the change in outline 

 and proportions with change in orientation, and an adequate 

 description becomes exceedingly difficult. 



Synonomy : Karsten (1907, December), has described as 

 Steiniella cornuta an organism which exhibits the form, propor- 

 tions, linear markings, and ventral excavation characteristic of 

 this species (Kofoid, 1907, April 11, 13). 



Comparisons: See G. poly gramma (p. 229). The earlier 

 figures (see Kofoid, 1907b, pi. 30, figs. 37-39) of this species are 

 of a more rugose specimen which, owing to escape of contents, is 

 somewhat collapsed and it therefore fails adequately to show 

 the typical rotundity of this species, or its usual delicacy of sur- 

 face markings. It varies towards G. kofokli Pavillard, but is 

 separable by the proximal curvature of the girdle, the ventral 

 excavation and the more rounded antapical outline. It is not 

 in our experience merely an accumulation of extreme variants 

 of the polygramma-kofoidi series, but a well-established species 

 with relatively few individuals which exhibit intergradations. 



Distribution : Sparingly present in the autumn ( October to 

 January) in oceanic plankton of semitropical facies. Associated 

 with Ccratiiim reticidatum, C. trichoceros and Ornithocercns 

 magnificus. Reported by Pavillard (1909) in the winter plank- 

 ton of the Gulf of Lyons, where it has its maximum in January. 

 Reported also by Karsten (1907) as Steiniella cornuta, from the 

 Indian Ocean, 9° 6' N, 53° 41' E in catch from 200 m. 



d). The Folyedra Group 



Characterized by polyhedral form, with angled sutures, 

 rugose surface, without longitudinal striae. No apical horn. 

 Plate formula 4', 2", (or 5', 0"), 5", 6, 6'", 1^, 1"" . 



Here belong Gonyaulax polyedra Stein and G. milneri (]\Iur- 

 ray and Whitting) Kofoid, originally described by Murray and 



