Mr. Hancock on the Anatomy of the Freshwater Bryozoa. 173 



cated by the above reactions. They likewise show the presence 

 of chloride of sodium, potash, sulphuric acid and magnesia. 



In comparing this secretion of the leaves of the Ice-plant with 

 the fluid in the ascidia of Nepenthes, we find a material difference 

 in their respective compositions, as will be seen by the annexed 

 table, which exhibits the composition of both fluids. : — 



Composition of the fluid in the Composition of the watery secretion 



ascidia of Nepenthes. of the leaves of Mesembryanthe- 



ffium crystallinum. 



Organic matter, chiefly malic and a Organic matter (albumen, oxalic 



little citric acid. acid, &c). 



Chloride of potassium. Chloride of sodium. 



Soda. Potash. 



Magnesia. SdpS acid. 



_ . 



XVIII. — On the Anatomy of the Freshwater Bryozoa, with de- 

 scriptions of three new Species. By Albany Hancock, Esq.* 



[With four Plates.] 



During a ramble made last July in company with "The Tyne- 

 side Naturalists' Field Club " to the Northumberland lakes, I was 

 fortunate enough to find two or three species of Bryozoa. Since 

 then I have revisited the locality twice, and on each occasion 

 additional species occurred. Thus six or seven forms of these 

 interesting animals have been found to inhabit two of these 

 lakes, namely Bromley Lough and Crag Lough. Three of the 

 species appear to be undescribed ; these I propose to characterize 

 towards the close of this communication, giving previously an 

 account of the anatomy of the freshwater Bryozoa so far as I 

 have been able to determine it. 



Amongst the known species was a fragment of Alcyonella, 

 most probably A. stagnorum; but its characters could not be 

 determined on account of the imperfection of the specimen. 

 Fredericella sultana occurred abundantly and of very luxuriant 

 growth, spreading over the under surface of stones in patches of 

 three or four inches' extent. Of the new species two belong to 

 Plumatella and one to Paludicella, a rare genus, of which there 

 was but one species previously known, and that I believe had 

 been found only in Ireland, and in two or three localities on the 

 continent. 



The anatomy of the freshwater Bryozoa had been very little 

 studied on this side of the Channel before Professor Allman took 

 up the subject, and he has handled it so well that little is left to 



* Read at a Meeting of the Tyneside Naturalists' Field Club, Dec. 1849. 



