224 



Ca-LEXTERATA 



Order II. Stauromedusae. 

 Best known are the LrCFKXu;i.i- ifi.^. iSo^ which lack marginal hociics. but 

 usuallv have four small icniacles in their place, while the adradial regions are 

 drawn out into arms, bearing bundles of tentacles. The aboral surface of the 

 bell is produced into a stalk bv which the animals are attached. The Tesse- 

 RID.E (,unknown in America) are free-swimming. 



Order III. Peromedusas. 



Free-swimniinL;, cup-shaned niedn,-;a-, with four interradial sense bodies; 

 mostly from the high seas. ririi\'!pa. Pcripliylia in Ckilf Stream. 



Order IV. Cubomedusae. 



DifTer in the four perradial sense bodies. Tropical and subtropical; develop- 

 ment unknown. CliarythUo (_hg. 190). 



Fio. iSo. — //ii/vi7v.s7h.s- iiuricuhvii'* 

 (after Clark). 



Fro. 100. — Charyhihu] nhir^upinlis 

 l^from llatschck). 



Order V. Coronata. 



A coronal furrow on the cxumbrella; four to sixteen marginal sense bodies as 

 in Disconiedus;c', l.)ut eight gonads and [irescncc of cathamma. Some of these 

 formerly regarded as Disconiedusx (tinck'r the name of Cannostomex), because 

 of eight sense bodies. Xausillior nlhida arises bv terminal Inidding from a 

 scyphostoma (Stcphaiioscvpliiis niirabilis) piarasitic in sjionges. .Holla. 



Class III. Anthozoa (Actinozoa). 



The Actinozoa, including the sea anemones, sea pons, and corals, 

 are exclusi\cly marine. \Mlh few exceptions they are sessile ami usually 

 form coloiyes, often of enormous size. In this ;is in appearance (fig. 192) 



