vor 



l,^'''] PROCEKI)IX(i.S OF THK NATIONAL MirREIIM. 183 



tain on iiccouiit of the contraction of the sju'ciniens. Tlioy seem to be 

 ninety-six in number,, and to bo arranged in two cycles of twenty-four 

 eacli, and one of forty- eigl it. Their longitudinal musculature is well 

 developed and is entirely ectodermal, sui)i)orted on strong mesoghcal 

 processes. The juesoghca of the tentach^s does not partake of the 

 fil>rous structnr«5 of that of the column wall, but is hyaline. 



Two sii)honoglyi)]ies are ])resent, apparently, and two ])airs of direct- 

 ives. There are foity-eight mesenteries, only the six inimary pairs 

 being perfect. The secondary and tertiary pairs Ix'ar the icproductive 

 elements, those of the foui'tli cyclel)eing(juile small an<l <lestitute of mes- 

 enterial fihiments. The longitudinal musch^ pidcesses are fairly well 

 developed, but do not Ibiin a. Ncry distinct muscle pennon. Acontia 

 are ])resent; in some of tlu^ specimens they were <'niitted from the 

 mcmth, but in none did [ find them protruding from tln^ column wall. 



On account of any failure to discover c;inclides it is of course doubt- 

 ful if this form is correctly referred to the genus Addiiisia. The shape 

 of the sphincter is decidedly ditferent from tliat oi' Adanifiia parasitica, 

 and A. poli/fms n>i, descril)ed by llertwig, but does not, however, differ 

 so materially from that of Adamsia >S'oi of our eastern coast. JVIy ])rin- 

 cipal reasons for considering .1. iiivolvens ax)ossibhi AdamMa is its hab- 

 itat on gasteropod shells and the secretion of a. strong chitinous mem- 

 brane by th(i ectoderm of tin; base, features which are, however, of com- 

 paratively small value. 



Subfamily ( iuoNDUAOTiNiNyio, liaddon. 



Sagartida; with thick (;okmin wall, usually with the upper portion 

 (capitulum) ditferent in character from the lower (scapus) and capable 

 of being entirely invected; the scapus provided with an external cuti- 

 cle and usually nodulated or warty; the sphincter stiong and ind)edded 

 in the mesoghea; only the six ]»rimary jtairs of nu'senteries perfect 

 and at the same time nongonophoric; acontia emitted by the mouth 

 only, there being no cinclides. 



(ipiiiis ACTINAUGE, \'.iiill. 



Choinlractinime in which the capitulum is i)rovided with longitudimd 

 ridges; scapus strongly tulx'i'culate or nodulate, tin; tubcicles n<'ar the 

 junction of the scapus and capitulum being usually stronger than those 

 lower down; each tentacle with a bulbous thickc^ning on the outer 

 surface at the base. 



This geims was established by Verrill ('.s;i) to receive a form which 

 hc! believed to l)e identical with the Actinia nodosa of Fabricius. The 

 deiinitiou given above contains the essential points of Verrill's defini- 

 tion, with the addition of a mention of the i)resence of a bulbous en- 

 largement at the base of the tentacles, a feature to which 1 1 addon 

 ('89) has called attention, and made an important factor in the limita- 



