70 PROCEEDINGS OP THE ACADEMY OF 



river, in mud. Duck creek, Del., mud. Rice field mud, Savannah river. 

 The variety most commonly met with is more broadly ovate than that figured 

 in Mic. Journ., vol. viii., and has a wide, smooth intercostal or more proper- 

 ly acostal space at the larger endof the valve. 



9. Amphiprora p u 1 c h r a Bailey. Sporangial of A. alat a? Hab. Entire 

 Atlantic coast, mostly in still or stagnant salt ditches or streams. It may be 

 observed of this species or variety, that in American localities it outnum- 

 bers the supposed typical form, A. al a t a , and more than once I have found 

 it in marshes where not a single frustule of A. a 1 a t a has ever been seen by 

 me. In the salt ditches along the Atlantic, N. J., railroad, A. pulchra is 

 a very common form, the frustules ranging in size from that of A. a 1 a t a to 

 the largest dimensions heretofore seen in the former variety, and yet these 

 smaller frustules have all the coarseness of striation and distinctive peculiari- 

 ties of the largest. The same holds good at another locality, Bannister's 

 creek, Rockaway, where, as well as at Absecom, A. a lata is very seldom 

 met with. While, therefore, it must be acknowledged that a certain general 

 resemblance, amounting almost to identity of species, exists between the two, 

 it might be well, in view of the above facts, to regard A. pulchra as a fixed 

 variety of A. a 1 a t a , and not its sporangium. 



10. Navicula p e r m a g n a Bailey. Pinnularia p e r m a g n a Bailey. Hab. 

 In most of our large Atlantic rivers and brackish marshes. At Cape May, 

 salt marsh near Cold Spring, abundant. A variety, illustrating the great 

 range of outline in this species, is seen in PI. II. f. 11. This is probably the Na- 

 vicula e s o x of Kiitzing. It is more common on the Delaware river and its 

 tributaries than that figured by Bailey. This form may be found exhibiting 

 every range of outline between the two extremes. The striation and length 

 of the frustule remains unaltered, however. 



11. Synedra undulata Bailey. Hab. Long Island Sound. On algae 

 from Newport harbor, Mr. Powel, very fine and large. Occurs in rice field 

 earth, Savannah river. 



12. Tetragramma am ericana Bailey (Terpsinoe am e r icana) Hab. 

 Atlantic coast of U. S. L. I. Sound, at New Haven. Black rock and Stoning- 

 ton, in mud. St. Mary's river, Ga., marsh. Delaware river, and at Bailey's 

 locality, St. Sebastian's river, Florida. Although a widely distributed species, 

 I have not found it in any abundance, except at the last named locality. Like 

 Terpsinoe musicaitisa brackish form, although often found in fresh water 

 streams. 



13. Terpsinoe musica Ehr. Hab. Southern coast, most some distance up 

 tidal rivers. Rice field mud, Savannah. St. Mary's river, Ga. Blue clay of 

 Delaware river. Very rare. 



14. Podocystis americana Bailey=(P. adriatica?) Hab. L.I.Sound. 

 Light House Point, Black Rock harbor, on algse. 



IV. Species of universal distribution along the coast. 



Epithemia musculus. 

 Cocconeis scutellum. 

 Coscinodiscus s u b t i 1 i s . 



radiatus. 



eccentricus. 



oculus-iridis. 

 Eupodiscus a r g u s . 



sculptus. 

 Triceratium f a v u s . 



alternans. 



Triceratium punctatum. 

 Cyclotella Kiitzingiana. 

 r otul a. 

 opercula t a. 

 Surirella f a s t u o s a . 

 gemma, 

 striatula. 

 o v a t a . 

 s a 1 i n a . 

 a ngust a . 



[March, 



