Freshwater Bryozoa, with descriptions of new Species. 201 



tapering to their origin, and attached for more than half their 

 length ; the enlarged extremity, being free and bending upwards, 

 inclines a little to one side, and is occasionally bifid, forming 

 two cells ; an obtuse ridge or keel extends the entire length of 

 the cell, increasing imperceptibly in thickness upwards ; orifice 

 somewhat constricted, the walls immediately below being pellucid, 

 and suddenly dilating become abruptly opake and thickly covered 

 for some distance downwards with agglutinated sand. Tentacles 

 forty-two in number, slightly tinged with yellow, the colour best 

 seen when they are formed into a compact bundle; membrane 

 at their base distinct, scalloped, the points being prolonged a 

 little up the tentacles. Egg black, long, oval; sides nearly 

 parallel ; margins pellucid, yellow, sharp, broad and reticulated. 



This species was procured rather abundantly in Bromley Lough, 

 and does not appear to vary much. At first sight large patches 

 of it have the appearance of being formed of a single polypidom ; 

 but on close examination are found to be composed of many, and 

 rarely to number more than six or eight cells in each. The com- 

 mencement of each polypidom has the black envelope of the ori- 

 ginating egg adherent. 



Two or three specimens of a more branched form of carinated 

 Plumatella were taken in Bromley Lough, which may probably 

 prove a distinct species ; more individuals however are necessary 



before it can be characterized. 



j 



Paludicella procumbens. PI. V. figs. 1 & 2, and PL IV. 



Polypidom membranous, subhorny, pellucid, smooth and glossy, 

 of a brownish horn-colour, much and irregularly branched, form- 

 ing large patches on the underside of stones, for the most part 

 adhering, with rather numerous, short, free, almost simple 

 branches ; the branches composed of a single series of narrow 

 cells arranged longitudinally, contracting towards the base and 

 widening upwards ; aperture lateral, near to the upper extremity 

 of the cell, forming a rather long and somewhat constricted tube 

 inclining upwards ; margin entire, surmounted by a widish, deli- 

 cate, hyaline, membranous cup. Tentacles sixteen in number, 

 arranged in a complete circle, and when spread out forming a 

 very exact inverted cone. 



This, the second species of the genus, resembles very closely 

 P. articulata of Allman, but that form appears to have about 

 twenty-six tentacles, and is likewise more densely and luxuri- 

 antly branched ; the cells, too, are larger and of a different colour. 



The P . procumbens occurred in both Bromley and Crag Loughs, 

 but most abundantly in the latter, where it spreads over the 

 under surface of stones in patches of 5 or 6 inches diameter. 



