234 BULLETIN OF THE BUREAU OE FISHERIES. 



III. Antipatharia. — Colonial zoantharia, usually with a hollow, branching skeleton of homy 

 nature. S") far as known, no representatives of this order occur in the region, which obviates the 

 necessity for further account of it in this report. 



SYNOPSIS OF TRIBES OF ACTINIARIA. 



EDWARDSIAE R. Hertwig, 1882. 



Noncolonial Actiniaria with eight mesenteries, two pairs of which are directives; others unpaired, 

 and their longitudinal muscles face the same direction; all mesenteries gonad bearing. Tentacles 

 simple, few in number, usually more numerous than the mesenteries, varying from 12 to 36. Column 

 more or less linear and cylindrical, often fluted along the lines of attached mesenteries. 



ZOANTHEAE R. Hertwig, 1882. 



Colonial Actiniaria, with numerous mesenteries of two sorts, namely, small, incomplete, and devoid 

 of gonads; large, complete, and gonad bearing. A single oesophageal groove. Outer surface of body 

 usually incrusted with a coating of sand or other foreign particles. Tentacles simple. 



CERIANTHEAE R. Hertwig. 1882. 



Actiniaria with numerous, unpaired mesenteries, except a single pair of directives, which are very 

 short and attached to the deep oesophageal groove. On either side of these will be found the much 

 longer perfect mesenteries, which increase in size in regular order to the opposite (dorsal) side. Tenta- 

 cles numerous and in two series — an outer principal and an inner accessory series — the circumoral tenta- 

 cles. Body elongate, usually inclosed in a slimy flexible tube. Aboral end of body rounded and 

 provided with a terminal pore. 



HEXACTINIAE R. Hertwig, 1882. 



Actiniaria with six or more pairs of primary mesenteries. Other cycles arise in pairs, some of 

 which may become perfect, others incomplete. The primary mesenteries are provided with retractor 

 muscle fibers on their inner faces i. e., the muscles of each pair facing the intraraesenterial space. 

 There are usually two oesophageal grooves, with directive mesenteries, whose muscles face outward, or 

 opposite the aspect of the other pairs. Body more or less smooth, often with longitudinal fiurows, and 

 in certain cases with wartlike nodular processes, verucae. Tentacles usually numerous and of various 

 characters. 



The above tribal characteristics have been variously compileQ from those given by Hertwig, McMur- 

 rich, Haddon, Duerden, and Gosse, and to a less extent from Andres, Verrill, and others. 



FAMILIES OF HEXACTINLE. 

 ILYANTHIDyE Gosse (in part), 1858. 



Body usually elongate, cylindrical, aboral end roimded and with somewhat constricted, bulblike 

 physa, but devoid of definite pedal disk. Tentacles simple and relatively few in number, or in some 

 cases numerous; sphincter weak. 



There is considerable uncertainty as to the constitution of this family, some authorities even exclud- 

 ing it altogether. Gosse, who established it, included under it the Edwardsise as well as the Ceriantheae. 

 Hertwig considers the family as intermediate between the Rdwardsiae and true Hexactinise, and so 

 ranks them in his system. (Op. cit., p. 92.) 



ANTHEID/E Gosse (in part), 1858. 



Hexactinise with well-developed pedal disk, often capable of expansion and inflation as a pneumato- 

 phore. (Cf . Ck>sse, Actinologea Britannica, p. 149.) Column generally smooth, sometimes with verucse; 

 tentacles long, very flexible, and disposed chiefly about the margin of the disk; mesenteries numerous; 

 sphincter muscle very weak, rendering difEcult any considerable contraction of disk or tentacles. 



