170 Mr. H. J. Carter on a Lacustrine Bryozoon allied to Flustra. 



those of fossil remains as yet unparalleled in interest and num- 

 ber in Indian geological research. 



It differs from Flustra in the form and arrangement of the 

 cells, and in not being erect; and from Membranipora and Le- 

 pralia in not being calcai'eous ; but it agrees with Flustra in the 

 latter character, and with Lepralia in being decumbent, — espe- 

 cially with that subdivision which has oral spines without other 

 external appendages. 



Fortunately the wet specimens that have reached me have 

 arrived in a condition sufficiently preserved to admit of my 

 describing, with the polypary or skeleton, the animal also, which, 

 under the designation of lacustris, will stand as follows : — 



Hislopia lacustris, H. J. C, n. sp. PI. VII. figs. 1-3. 



Poljrpary kerato-membranous, without admixture of calcareous 

 matter. Cells irregularly ovate, compressed, spreading in 

 aggregation over smooth surfaces, sometimes linearly, but for 

 the most part with no definite arrangement. Aperture sub- 

 quadrangular, supported on a circular neck, closed by four 

 triangular valves, of which the posterior is the largest, and 

 partially overlaps the rest; surrounded by a horny raised 

 border, from the angles of which respectively four spines 

 project ; posterior border less prominent than the rest, which 

 permits of an almost uninterrupted continuation between the 

 larger valve or lip and the membranous portion of the cell. 

 Margin of the cell horny, pierced by 2-4 stoloniferous holes. 

 Average greatest length and breadth of the cell l-29th and 

 l-38th of an inch respectively. 



Hah. Freshwater tanks which are never dry, on Paludina ben- 

 galensis and the stems of aquatic plants. 



Loc. Nagpoor in Central India. 



Animal. — Contained in a membranous sac, which lines the cell, 

 and communicates with 2—4 adjoining cells by stolons through 

 the holes mentioned : viz, posteriorly with the mother-, and 

 anteriorly and antero - laterally with 1-3 daughter-cells. 

 Mouth triangular, bordered by the valves mentioned, leading 

 into a delicate, transparent, buccal sheath, plaited anteriorly, 

 at the bottom of which (when inverted) is the orifice of the 

 throat surrounded by 16 (?) tentacula. Pharynx pyriform, 

 presenting a layer of cells or follicles internally, extending to 

 the commencement of the oesophagus, which is narrow, long, 

 and bent upon itself. (Esophagus followed by a dilated, 

 globular portion, called the 'gizzard,^ which is thick-coated, 

 presenting two linear, horny bodies internally, and opening 



