OBSERVATIONS ON POI.YZOA. 



203 



According to this view of their relations, the Phylacto- 

 l^mata comprise three families, or subgroups. First; 

 the FredericelUdce, founded upon the great differences be- 

 tween the lophophore and nervous system of Fredericella, 

 and the members of the other families. Second ; the Plu- 

 matellidce, which differ from the Fredericellidee in the lopho- 

 phore and nervous system, and from the Cristatellidae in 

 their coencecial characters. Third ; the Oristatellidce, whose 

 coenoecia and mode of development separate them widely 

 from both the preceding. 



The following is a scheme of this classification, enumer- 

 ating the families and genera by name, and the number of 

 species at present known in America, Europe, India and 

 Australia. 



■a) W 



.5 -2 



>5 -«; 



fc - 



fk e deeicellid-e . 



plumatellidje. 



Cristatei.lid.k. 



3 



1 









13 





1} 



1 





1 





111 



o 



1 





12 Hi l l :;o 



*Plumatella includes Alcyonella, which is only a variation of the ordinary form of 

 the species. 



fA species of Plumatella mentioned, but not named or described, from Melbourne, 

 and the vicinity of Richmond. D. Oyly H. Alpin. Ann. and Mag. Nat. Hist. 3d Ser. 

 Vol. 6, p. 454. 1800. 



JA species mentioned by Dr. Leidy. Proc, Phil, Acad. Nat. Sciences, Vol. 10, p. 190. 



|| A. statoblast, found near Bombay and described by Mr. J. H. Carter in the Ann. 

 and Mag. of Nat. Hist. Vol. 3, p. 341, pi. S, f. 8-15, 1859, supposed by him to belong to 

 Lophopus crystallinus. It, however, undoubtedly belongs to a new species of Pec- 

 tinatella, and I therefore propose fqr this new species, which is remarkable for its 

 spines, furnished with many lateral hooks, growing only from the ends of the stato- 

 blast, the name of Pectinatella Carteri. 



