200 Mr. A. Hancock on the Anatomy of the 



muscular arrangement. Thus the Bryozoa become related to 

 the Lamellibranchiata, which are apparentlyclosely related to the 

 Brachiopoda. We may conclude then, if we have arrived at a 

 right understanding of the affinities of these animals, that both 

 the Mollusca and Vertebrata are connected with the Bryozoa. It 

 would be well therefore to pause before including the Bryozoa in 

 the Mollusca, and consider the propriety of uniting the former 

 with the Tunicata, and perhaps with some of the higher forms of 

 Rotifera, into a group to be placed at the head of the Radiata. 



Descriptions of new Species. 

 Plumatella punctata. PI. V. figs. 6 & 7, and PL III. fig. 1. 



Polypidom adhering throughout, coriaceous, pellucid, of a pale 

 watery green colour, irregularly but not much branched, seldom 

 extending more than half an inch ; branches composed of a series 

 of large, conical cells tapering upwards towards the aperture, 

 sometimes considerably and rather suddenly dilated at the base ; 

 resembling in form some of the Ascidians ; the upper portion of 

 the cell almost colourless and freckled with minute opake white 

 spots, most crowded towards the orifice. Tentacles white, not 

 more than sixty in number; membrane at their origin rather 

 wide, scalloped, the points of the scallop extending for some di- 

 stance up the back of the tentacles in the form of broadish laminae 

 arched outwards. (Esophagus and stomach appearing through 

 the transparent walls of the cell of a pale yellow colour. Egg 

 perfectly black, large, broad and oval. 



Upwards of a dozen specimens of this fine species occurred in 

 Bromley Lough, adhering to the underside of stones ; it was like- 

 wise taken in Crag Lough. None of the individuals much ex- 

 ceeded in size that represented in the figure, nor did they vary 

 in any remarkable manner either in form or colour. It is not, 

 however, without hesitation that I have ventured to characterize 

 this as a new species, as Professor Allman informs me that it 

 may perhaps turn out to be P. repens ; but that form is stated 

 to be large and of luxuriant growth, and to have the polypidom 

 tubular with the cells dilated at the orifice — characters which do 

 not at all agree with P. punctata. Indeed it can scarcely be 

 considered a true Plumatella. 



P. Allmani. PI. V. figs. 3 & 4, and PI. III. figs. 2 & 3. 



Polypidom attached to the underside of stones, adhering 

 throughout, membranous, opake, yellowish brown, slightly 

 branched, extending in patches sometimes three or four inches 

 wide, the patches being made up of several polypidoms; the 

 branches composed apparently of a series of tubular cells, 



