492 PROCEEDINGS OF THE ACADEMY OF [1881. 



at various times upon conchologieal subjects, at meetings of the 

 Academy, by Dr. Leidy and Messrs. Heilprin, Ryder and Ford. 



Our Conservator, Mr. Tryon, reports that 



" During the year ending December 1, 1881, forty-four distinct 

 donations of recent shells and mollusks have been received, 

 aggregating 877 species, represented by 3205 specimens. With 

 the assistance of Mr. Charles F. Parker these have all been labeled, 

 mounted and displayed in the Museum. In addition to this work, 

 the rearrangement of the entire collection, in accordance with the 

 latest and best views of classification, which was commenced two 

 years ago, is constantly progressing — the Turbinellida?, Nassidae 

 and MitridsB having been completely re-studied and partly 

 re-labeled. 



' The collection of Unionidae having outgrown the limits orig- 

 inally assigned to it, a new arrangement thereof became necessary, 

 and for this purpose ninety-six drawers were appropriated, at the 

 west end of the Conchologieal gallery. The specimens are now 

 uniforml}- mounted, with new labels, and classified in accordance 

 with the latest edition of Dr. Lea's Synopsis of Naiades. Two 

 reference-catalogues of the family have been prepared, one of 

 which is for the use of strangers desirous of consulting the col- 

 lection. The cabinet of Unionidae contains over six hundred 

 species, represented by several thousand selected specimens, and 

 occupies two hundred and forty feet of surface space. To the 

 above work Mr. Parker has, as usual, devoted much of his time, 

 and with great advantage to the appearance of the specimens. 



" Early in the year an opportunity occurred to secure a fine 

 suite of fossil shells from the older formations of the West — 

 hitherto very imperfectly represented in the Academy's Museum ; 

 the Section obtained these by purchase. 



" Prof. Angelo Heilprin having assumed official charge of the 

 cabinet of invertebrate palaeontology, his annual report will con- 

 tain the summary of donations of fossil shells, heretofore included 

 in this report. 



" Recently, a large and valuable selection of recent shells, all new 

 to the Academy's collection, has been offered to us at a reason- 

 able price, and by the kindness of several friends, a portion of it has 

 already been secured. In this connection we would call attention 

 to the manifest impossibility of maintaining unimpaired the use- 

 fulness to students of our Conchologieal collection by continuing 



