186 Wisconsi7i Academy of Sciences, Arts, and Letters. 



task. The Poljp or Bryozoan cells seldom exceed a hundredth 

 of an inch, and in some species are less than a two hundred and 

 fiftieth of an inch in diameter. The cell walls and interspaces 

 are often dotted with pits or pores, the tabuli of some authorities, 

 or studded with granules, whose dimensions are from one-half to 

 one-tenth of the diameter of the cells. In the illustrated draw- 

 ings these surface markings are enlarged from twenty to fifty 

 diameters. 



The term corals, as applied to these forms, does not necessarily 

 imply that they belong to the radiate sub-kingdom. We find, in- 

 deed, that Professor Dana includes under this general term calca- 

 reous or honey structures formed not only by Polyps andHydroids 

 (Eadiates), but by Bryozoans (Mollusca), and also by certaio 

 low vegetable forms. 



In the classifications that have been made, the widest diversity 

 exists ; no two authorities seem to agree, and the same species is 

 relegated even to different sub-kingdoms by leading naturalists. 

 Of the thirteen genera recognized in this collection. Professor 

 Whitfield has placed Chceteies, Alonticulipora, StelUpora, Alveo- 

 lites and Dekayla under Corals ; and Trematopora, Fistulipora, 

 Palceschara, Stictopora, Fenestella, Reiopora, Alecto and Aulo- 

 pora under Bryozoans. S. A. Miller, of Cincinnati, classes the 

 first group as Eadiates of the Favosite group, Fistidipora as a 

 Millepore, Aidopora as an Alcyanoid coral, and the remainder 

 Bryozoans. Professor Dana differs from others in considering the 

 Chcetetes and related genera Hydroids instead of Polyp corals, 

 while Dr. Rominger, of Michigan, throws them out of the Radiate 

 sub-kiogdom altogether, and places the whole list under Bryo- 

 zoans. The close relationship and gradation of forms observed 

 in our specimens indicate that they should not be separated into 

 as widely differing divisions as has heretofore been done. 



Before considering this matter further, we will notice the rela- 

 tionships that exist between some of these forms. Beginning 

 with those genera that are considered by all authorities as belong- 

 ing to the Bryozoan order of Mollusks, we first notice the two 

 representatives oi the genus Stictopora, that are found in this col- 

 lection. (Fig. 1 represents S. elegantula, and Fig. 2 S. fragilis.) 



