122 ZOOPHYTES. 



an oval form. Nevertheless it is not to be assumed that such extraordi- 

 nary dimensions belong unequivocally to a single specimen, for the margin 

 of two might meet in the course of their mutual diffusion. However, 

 many of inferior extent were undoubtedly single and entire. Several short 

 tubular projections were crowded together near the centre of some fine 

 specimens. The angular extremities terminated in several hydra?, which 

 appeared dingy white when retracted ; then the surface seemed to be com- 

 posed of ill-defined pentangular cells. 



This Alcyonella diffused in a superficial stratum over the white paint- 

 ed wood, dark streaks denoting the hydra replete with mud, which gave 

 great variety and interest to the objects. Some of the strata near the 

 keel of the boat were thicker, possibly being better sheltered, and were 

 there four lines deep. 



The hydra? were very numerous. Besides a notch at the summit of 

 the body, I thought, that under the microscope, an orifice might be dis- 

 covered in each side of the integument near the summit. Were there no 

 illusion here, it would help to explain how the ova may escape while the 

 animals are yet entire. A few were visible. Eight ligaments appeared to 

 be the number connecting the body with the stratum below. 



Though averse to precipitate conclusions, while stating at large the 

 impressions received, I am induced on the whole to conclude, that the pro- 

 ducts described in the present paragraph nearly correspond with the na- 

 ture of the Alcyonella recovered from the pond in 1831. 



Yet there are certain discrepancies to be reconciled, which deserve 

 more profound investigation than I have had an opportunity of devoting 



to them. 



Should these three Alcyonella) be truly three different species, they 

 may be distinguished by three different names. Should the whole merge 

 in one, as future opportunities, better skill, and observation of other natu- 

 ralists shall determine, the Alcyonella stagnorum must be alone retained. 



Meantime various interesting physiological facts will remain immu- 

 table. 



Plate XXX. Fig 1. Alcyonella gelatinosa investing an old branch. Fleshy pro- 

 tuberances a, J, c. 



