NATURAL SCIENCES OF PHILADELPHIA. 63 



Hah. St. Mary's river. Ga., salt marsh and in tidal mud. Wharf at Fer- 

 nandina, Florida, tidal deposit. Pier at St. Augustine, Florida. Rare. 



3. Surirella F e b i g er ii, n. sp. F. V. As in last described. V. Ellipti- 

 cal to linear ovate, sometimes broadly sphenoid, alse inconspicuous, canalicul i 

 6 a 7 in "001, straight or slightly convex, linear, reaching from the margin to 

 a striated arcuate band situated relatively to the valves as in the preceding. 

 Interspaces of the canaliculi strongly punctate. Central portion similar in 

 outline to that of S. or n ata , elevated above the surface of the valve and 

 coarsely striate. Length of valve *006 a '010. PI. I. f. 2. 



The striking similarity in outline and number of canaliculi of this to the 

 last described species, together with the correspondence in both of the arcuate 

 striated bands, at first led me to regard these forms as merely different aspects 

 of the same frustule (valve) ; but after careful examination of several detached 

 valves, by reversing the slides and other manipulations, I am led to con- 

 clude that they belong to different species. Both are very striking and showy 

 forms, more particularly the last, whose strongly marked intercostal puncta, and 

 the generally ornate character of its valve, make it a singularly beautiful mi- 

 croscopic object. S. Febigeriiis pretty generally, but not abundantly, dis- 

 tributed along the Atlantic coast. The first specimen? were detected by me 

 two years ago in mud dredged from New London Harbor, sent me by Mr. Fe- 

 biger, of Wilmington, Del., in honor of which careful and industrious observer 

 I have named the species. 



Hah. New London Harbor mud, St. Mary river, mud from oysters. Wharf 

 at Fern'andina, and more recently at Cape May salt marshes, by Mr. Febiger. 

 From its wide range of locality it will doubtless prove a common form on the 

 coast. 



4. Surirella o v a t a , Kiitz, Sporangial ? PL I. f . 3. This variety is not un- 

 common in salt marshes along the Jersey coast, although specimens of the 

 size figured are very rare. A comparison with the typical species will show 

 considerable points of difference, but these become less in frustules which ap- 

 proximate to the normal size, although never altogether lost. It is perhaps 

 entitled to rank as a variety of S. o v ata. Length of valve '0009 a - 0050. 



5. Cymatopleura m ar in a, n. sp. F. V. Linear, slightly inflated ends more 

 or less truncate. V. Lanceolate, very acute, undulations from ti to 13. Sur- 

 face of valve irregularly punctate. Length of valve "0007 a "GO. PL I. f. 4. 



This inconspicuous little form, although not yet found in quantity, occurs at 

 various points along Long Island Sound. As far as is known to the writer it 

 is the only marine species. 



Hab. On alga? at New London. New Haven and Black Rock Harbors. East 

 river (Mr. Febiger), in mud. 



6. Amphiprora conser t a, n, sp. Frustules adherent in curved bands of- 

 ten to the number of 12 or more. Frustule straight, membranaceous. F. V. 

 Linear oblong, slightly dilated. Keel or ala central or subcentral, constricted, 

 costate, spathulate at extremities. V. Lanceolate or lanceolate with produced 

 extremities. PL I. f. 6. 



The great variation in size, outline and general configuration of the frustules 

 of this species, together with the fact of their being so imperfectly silicious that 

 a boil ng in weak acid either distorts or entirely destroys the specimen, ren- 

 ders it not improbable that this may be an early developmental form, although 

 of what known species, if any, would be difficult to say. A smooth and very 

 diaphanous variety of A. p a 1 u do s a occurs in the same gathering. 



The " plates " alluded to by the late Prof. Gregory (Marine Diatomacese of 

 Clyde,) as characterizing A. lepidoptera, and others of the genus, are 

 strongly marked in this species, and serve as a point of attachment between the 

 various frustules. Arising from the surface of the valve at a short distance 

 from its extremity, they are broadly convex and incline somewhat outwards. 



1861.] 



