OF CONCHOLOGY. . 291 



Freshwater Mollusca. 4. Land Mollusca. Of the land Mollus- 

 ca, Mr. Bhxnford states that, " but a very meagre series was ob- 

 tained, the country being evidently excessively poor in land- 

 shells. No Cyclostomacea have ever been found in this part of 

 Africa, and the large Achatintc and their allies were entirely 

 wanting in the country traversed, although they appear to have 

 been found further to the southwest, near Lake Dembea. 

 No new species are described. 



Transactions of the Royal Irish Academy. Vol. XXIV. Part XI 



Dublin, 1860. 



On the Histology of the Test of the Class Palliohranchiata. 

 By Prof. W. King. 



Conchologla Iconlca. Parts 282, 283. London, IS'ZO. 



Anodon. Plates 25 — 37. Completing the monograph. 



The following are described as new : 



^4. tricostatus, Sowerhy. China. 



A. Rio Flatensis, Sowerhy. Rio de la Plata. 



As A. alatus, Lea, is figured and described the Spatha alata 

 of Lake Nyassa. The difference between A. imbecillis Lea and 

 A. incertus Say are carefully pointed out, but the two species 

 are identical nevertheless. 



Species 103, A, Burroughianus, Lea, from Isl. Luconia near 

 Manilla, has a curious synonymy, namely, A. ohlitus, Lea, from 

 East Tenn. and a A. kennicottit Lea, from Great Slave Lake ! 



Sp. 106, A. pholadiformis, Sowerby, N. Sp. from Montreal. 

 I do not think this is distinct from A. irisans, Anth., published 

 in this Journal, vol. 1. 



Sp. 107, A. subgibbbsus, Anthony " MSS." Published in this 

 Journal, vol. 2, 144, 1866. 



Sp. 110,^. quadriplicatiis, Sowerby, Nov. Sp. Potomac River, 

 is not even an Anodonta ; it is known in this vicinity under the 

 name of Margaritana undulata, Say, is one of the commonest 

 and best known of American species, and has been figured by 

 Sowerby already under the latter specific name. 



Sp. 112, A. Williamsii, Lea. It is possible that this is a 

 strangely formed young shell of that species, for the figure is of 

 that convenient style of execution that will allow of a reference 

 to almost any species. It is not half the size of an adult Wil- 

 liamsii and its beaks are much too prominent. The river Poto- 

 mac is not in Georgia, as stated by Sowerby. 



