251 



March 6, 1850. 



The President in the Chair. 



Thirty-three members present. 



Mr. Girard exhibited drawings and read descriptions of 

 several new species of Marine Planariae of the coast of 

 Massachusetts. 



PoLYSCELis VARIABILIS Glravd. This species is oblong 

 shaped, somewhat lanceolated, of a color varying from a light 

 greenish yellow to an orange red, with a minute punctulation of 

 a deeper red. The relative position of the eye specks is sub- 

 ject to some variation. I have found it in Boston and Beverly 

 harbors, always in deep water. It spawns in January and Feb- 

 ruary. Entire length, half an inch. 



Prosthiostomum gracile Girard. It differs from other species 

 of the same genus by its very slender body and the arrangement 

 of the eye specks, which are disposed in four groups ; of which 

 the first and second are in a single pair, the third triple, and the 

 fourth double. From Boston Harbor. 



Procerodes Girard (nov. gen.). Body regular, sides nearly 

 parallel. Anterior region, (head,) separated from the body by a 

 kind of a neck. There are two tentacles in front, as in Proceros, 

 from which it differs, however, by the number and position of 

 the eye specks, of which it has but two. The general form is 

 very different from that of Proceros. 



P. Wheatlandii Girard. The only species of the genus yet 

 known. It does not exceed two lines in length, is of a brownish 

 color, and very lively in its habits. I found it last August at 

 Manchester, on the Beach at low tide, in company with Dr. 

 Wheatland of Salem, to whom I dedicate this species in recog- 

 nition of his zeal as a naturalist. 



Planocera elliptica Girard. This species I have mentioned 

 before the American Association for the Advancement of Sci- 

 ence when describing its embryology. It is quite common on 

 the sea-coast of Massachusetts. Its greatest size is about three 



