398 DR F. A. BATHER. 



end, since this is more marked than in any species except D. rossica, from which 

 D. paradoxica differs in the absence of a keel. 



Billings gives the greatest diameter of the distal region as a line and a half, 

 i.e. 3 mm. ; the length of the ossicles as drawn is TQ mm. or less. In all the other 

 species the length of the dimeres in the distal region considerably exceeds the diameter 

 of the stem. 



The proximal region seems to have been annulate, and the rings closer than in 

 other species. 



Billings' description of the columnals as forming "a tube " indicates a wide lumen ; 

 but this may refer mainly to the proximal and median regions. 



From these details of structure, there can be no doubt as to the distinctness of the 

 species. At the same time, as I suggested in 1900, it is almost certainly a Dendro- 

 cystis, and as such of much interest to the student of distribution. (See further 

 §§ 42, 562.) 



Fam. nov, Cothurnocystidae. 



§ 160. Diagnosis. — Amphoridea Heterostelea with a compressed theca of boot- 

 shaped outline, framed by marginals, between which stretches a finely-plated 

 integument ; with vent and intake both on the same face of the theca, the vent at the 

 end of the leg of the boot, the intake in the form of several openings, arranged in a row 

 near the toe of the boot, and each connected with a short subvective groove ; with a 

 stem attached to the sole of the boot,, at the hollow of the foot, comprising three regions, 

 a wide proximal composed of dimeres, a median consisting of a conical reducing piece, 

 and a distal composed of cylindrical columnals gradually tapering. 



§ 161. The Family at present contains only one genus, which, in allusion to the 

 boot shape of the theca, is named from Kodopvoi;, cothurnus — 



Cothurnocystis n.g. 



Diagnosis. — Same as that of the Family. 



Genotype. — Cothurnocystis Elizae (§ 170). 



Other Species. — Cothurnocystis curvata (§ 208). 



§ 162. Description of the Genus. — This summary, though involving much repeti- 

 tion, seems necessitated by the strangeness and novelty of the structure. For the sake 

 of clearness and brevity, some expressions connoting a certain habit of life are here 

 employed, although the arguments by which they are justified have to follow the 

 detailed descriptions of the species. 



The flattened Theca, of boot-shaped outline, and with a general structure indicated 

 above (§ 160), lay on the sea-floor, always with the same face undermost. 



§ 163. Viewed from this Under or Reverse face (text-fig. 14), the elongate gutter- 

 shaped Marginals are seen to form a complete Frame ; and this is kept rigid by a Strut, 

 made up of a downward process from a marginal on the instep meeting an upward 



