Part I1.—Stichodactylinee and Zoanthec. 187 
gland cells, both in the ectoderm and endoderm is noteworthy ; and also the very 
large, oval enidocysts in the knobbed tentacles, stomodzeal ectoderm, and mesen- 
terial filaments. The mesoglcea is an exceptionally homogeneous layer, and the 
retractor muscle of the mesenteries is arranged on only slight mesogleeal folds, 
never becoming circumscribed. Undoubtedly one of the most important ana- 
tomical features is the absence from the mesenterial filaments of any lateral 
lobes bearing the Flimmerstreif. 
Tribe.—ZOANTHE, R. Hertwig, 1882. 
Family.—Zoantuipm, Dana, 1846. 
Sub-family.—Macrocnemin®, Haddon and Shackleton, 1891. 
For the definitions of the Tribe, Family, and Sub-family, the first instalment 
of this series should be consulted, or better, the original papers of Haddon and 
Shackleton (1891, 1891 a). 
Genus.—_PARAZOANTHUS, Haddon and Shackleton, 1891. 
Macrocnemic Zoantheze, with a diffuse endodermal sphincter muscle. The 
body-wall is incrusted. ‘The ectoderm is continuous. Encircling sinus as well as 
ectodermal canals, lacune, and cell-islets in the mesogleea. Dicecious. Polyps 
connected by thin ccenenchyme, rarely distinct. 
The characters of greatest generic importance are the macrocnemic arrange- 
ment of the mesenteries, a feature shared with the genus Epizoanthus, and the 
presence of a diffuse endodermal sphincter muscle. 
In their “‘ Review of the British Actiniz,’ Haddon and Shackleton assign to 
the genus three European forms; P. avinelle (Schmidt), P. anguicomus (Norm.), 
and P. Dizoni, n. sp., and, in their Report on the Zoantheze collected by Professor 
Haddon in Torres Straits, make an addition of two new species, P. dichroicus and 
P. Douglast. In the paper on Jamaican Zoanthezx, I show that the Gemmaria 
Swiftii, of Duchassaing and Michelotti (1860), must be transferred to Parazoanthus, 
and also advert to the fact that Carlgren (1895) has demonstrated that the supposed 
Antipatharian genus Gerardia, Lac.-Duth, must probably be regarded as belonging 
to the same genus. Reviewing the Zoanthean genera in his latest paper, Haddon 
(1898, p. 408) confirms Carlgren’s statements with respect to this form, and 
locates Gerardia between the genera Parazoanthus and Epizoanthus. 
Recent trawling in the Caribbean Sea has brought up from the Pedro Banks 
distant about 50 miles south-west of Jamaica, a branching Hydroid over 100 cm. 
in height, the trunk and main divisions of which are entirely incrusted with a 
single Zoanthid colony. It bears a very close external resemblance to Parazoanthus 
