138 CCELENTERATA 



Family 2. FUNICULINIDAE. 



Sea pens. Stalk short and thicker than the quadrangular rachis 

 which is long and slender and bears the autozooids in oblique rows; 

 autozooids retractile; siphonozooids confined to lower side of rachis: 

 1 genus. 



FUNICULINA Lamarck. With the characters of the family : 2 species. 

 F. armata Verrill. Length up to 60 cm.; auto- 

 zooids deep purple; rachis yellowish below and 

 brownish above: Newfoundland to Nantucket, in 

 100 to 400 fathoms. 



Family 3. EENILLIDAE. 



Rachis broad and circular or reniform, with 

 the polyps confined to the upper surface; no axial 



skeleton: 1 genus. 

 Fig. 224 

 Renilla remformis Renilla Lamarck. With the characters of the 



(Cambridge Natural family: 10 species. 



R. reniformis (Pallas) (Fig. 224). Upper part 

 pink or violet in color, polyps white; 7 cm. long: on the Carolina coast, 

 in shallow water; West Indies. 



Order 2. ZOANTHARIA. 



Stony corals and sea anemones. AntJiozoa, often of large size, most 

 of which secrete a stony or horn-like skeleton. The tentacles are usually 

 simple (in the Australian sea anemone, Actinodendron, branched) and may 

 number from six to several hundred. 



The mesenteries (Fig. 220) are usually numerous, consisting of six 

 primary pairs (protoenemes) which alone are present in the most primi- 

 tive forms, and numerous secondary mesenteries (metacnemes) which 

 are usually unilateral, that is, in pairs, both members of which are on the 

 same side of the gullet, and arise in series, the younger and smaller pairs 

 appearing between the older and larger ones. The gullet is joined with 

 the body wall by all of the protoenemes (except in Edwardsia) and usually 

 by certain of the metacnemes, the two pairs of protoenemes which join 

 the siphonoglyphs with the body wall being called the directives. The order 

 contains 1,500 species, grouped in three suborders. 



Key to the suborders of Zoantharia: 



fli Skeleton present ; animals mostly colonial. 



bi Skeleton horn-like 1. Antipatiiaria 



l>2 Skeleton calcareous 3. Madreporakia 



Oj No skeleton ; animals mostly solitary 2. Actiniaria 



