ANATOMICAL CHARACTERS OF PEROPHORA HUTCHISONI. 379 



EXPLANATION OF THE PLATE. 

 Tab. LXV. Div. II. 



Fig. 1 . A sprig of Amphibolis, with Peruphora Hutchisoni climbing over the stem and leaves. 



a. a. Drooping branches. 



b. Solitarj' Ascidian, usually occurring with Perophora, and, like it, having a thin test closely 

 covered with sandy particles. [I have reserved the more particular description of this species 

 for a separate communication.] 



c. Encrusting Polyzoon. 



Fig. 2. A growing branch, magnified to show the disposition and mode of gemmation of the zooids. 



a, Growing point, always slightly in advance of 



b, b. The gemmations. 



c, d, e. Zooids further advanced, with the gritty coating removed. 



f. Corneous tubular axis. 



g. Epithelial lining of/. 



■ h. Pallio-vascular membrane. 

 Fig. 3. One of the zooids, more highly magnified. 



a. Corneous axis. 



b. Lining membrane of n. . 



c. Pallio-vascular canal. 



d. d. Articulations of the pedicel. 



e. The test, showing the pitted surface remaining after the removal of the gritty matter. 



f. Branchial orifice, and 



g. The cloacal orifice (both somewhat contracted). 

 h. Endostyle. 



i. Branchial sac. 

 j. Cloacal chamber. 

 k. (Esophagus. 

 /. Stomach. 

 m. Intestine, embracing the generative organs in its flexure. 



3u 2 



