120 ZOOPHYTES. 



species and unattached coralligenous species ; and the latter, " Plant Zoophytes" the 

 attached coralligenous species. 3 



The order Zoocorallia includes the following subdivisions : 



Tribe I. Zoocorallia Polyactima. Comprises his families Actinina, Zoanthina, 

 and Fungina, corresponding respectively to the families Actinidoe, Zoanthidoe, and the 

 free Fungidse, along with the genus Turbinalia of the Caryophyllia tribe. 



Tribe II. Zoocorallia Octactixia, or species with 8 rays to the polyps. Com- 

 prises his families Xenina, Tubiporina, Halcyonina, and Pcnnatulina, or all the Alcyo- 

 naria but the Gorgonidoe, which fall into his second order. 



Tribe III. Zoocorallia Oligactinia, corresponding to Hydroidea, and including 

 his families Hydrina, Tubularina, and Sertularina. 



The order Phytocorallia, is subdivided as follows : 



Tribe IV. Phytocorallia Polyactinia. Includes the families Ocellina, and De- 

 dalina ; the former corresponding to the Caryophyllidse and Cyathophyllida?, except that 

 the Turbinaliae are excluded by Ehrcnberg, and some Astrasas are introduced under the 

 genus Explanaria ; and the latter corresponding nearly to the Astrasidse and Fungidse, 

 except that the free Fungidas are separated. 



Tribe V. Phytocorallia Dodecactixia. Comprises the families Madreporina and 

 Milleporina, the first including the Poritidse and part of the Madreporidre, and the second, 

 the remainder of the Madreporidse of the system adopted. 



Tribe VI. Phytocorallia Octactinia, including the families Isidea and Gorgonina, 

 corresponding to the Gorgonidse. 



Tribe VII. Phytocorallia Oligactinia, including the single genus Allopora. 



This system removes the free Fungidoe far from the attached species, and the same 

 principle carried out should place in different families the free and attached Cyathophylla, 

 Euphyllise, and others. The natural group Alcyonaria is divided, and the parts are 

 widely separated. Notwithstanding these singularities arising from the undue importance 

 allowed to the characters of his Orders, the system exhibits throughout the comprehensive 

 acumen of its distinguished author, and was the first that rested its distinctions solely on 

 the structure of the animals, or the living zoophytes. 



Milne Edwards. — In the philosophical system of Milne Edwards, the Bryozoa con- 

 stitute the order Polypes tuniciens ; and other Zoophytes (our Zoophyta), his Polypes 

 parciirlniiiiiilcx. This second order he subdivides as follows : 



1. " Sertulariens." Corresponding to the Hydroidea. 



2. " Zoanthaires" Corresponding to the Actinaria. 



3. " Akyoniens." Corresponding to the Alcyonaria. 



The Aleyonia group, which is bound together by important characters, is thus kept 

 united ; and the other groups are equally well defined in their limits and characteristics. 

 The " Zoanthaires" and " Alcyoniens," constitute together our Actinoidca, a group which 

 is equivalent, as a whole, rather than its parts, to the " Sertulariens" (Hydroidea). 



' These orders are characterized by Ehrcnberg as follows (op. cit., pp. 255, and 299) : 

 Zoocokallta. Corpore ant omnino molli, nut. Cephalopodum more intus lapidem gencrante (sccernente 

 nee < xeerncnte) hinc sa'pc omnino libera ct, prater formain, animalium charactcres omncs perfectius 

 servantia. Phytocorallia, Corpore aut lapideam aut corncam materiam agglut'mantem sccernente ac 

 dorso (solea) excernente cjusque ope semper adnato (Ostrearum more). 



