THE DIATOMACE^ OF PHILADELPHIA AND VICINITY 69 



TROPIDONEIS LEPIDOPTERA (GREG.) CLEVE 



Valve with straight, median excentric line. Keel unilateral, projecting above the 

 median line in zone view; central area small. Transverse striae finely punctate. As usually 

 seen, the valve is inclined. According to Karsten there are two chromatophores on the 

 connective zone, each divided into four parts, each of which contains a large oval pyrenoid. 



Amphiprora lepidoptera Greg. 



Along the coast. 



PL 14, Figs. 8 and 9. 



AURICULA CASTRACANE (1873) 

 (auricula, the ear, the shape of the valve) 



Frustule globose. Valve reniform or cymbiform, elevated into a keel which is not 

 sigmoid. Median line biarcuate. Differs from Amphiprora in not having a sigmoid keel. 



AURICULA MUCRONATA (H. L. SMITH) PERAGALLO 



In zone view, the median line deeply bisects the longitudinal axis, ending in a mucro- 

 nate central nodule. Connective zone complex. Valve very complex, with ventral margin 

 nearly straight and raphe excentric. Central nodule near the margin, terminal nodules 

 small. Striae, 35-40 in 10 n (Cleve). Chromatophore single, on the ventral part. 



Amphora mucronata H. L. Smith. 



Amphora (?) insecta Grun. 



Auricula insecta (Grun.) Cleve. 



"A rare and very curious pelagic species" (Peragallo, Diat. Villefranche). 



Prof. H. L. Smith included this form in his first century of "Species Typicae Diatom- 

 acearum," which was issued prior to 1876, the date of publication, in Schmidt's Atlas, of 

 Amphora insecta Grun. 



Atlantic City, N. J. Rare. 



PL 15, Fig. 2. 



SCOLIOTROPIS CLEVE (1894) 

 (scolios, twisted, and tropis, a keel) 



Frustule linear, oblong. Median line sigmoid near the ends. Valve with transverse 

 costse alternating with two intermediate rows of puncta in oblique lines. 



SCOLIOTROPIS LATESTRIATA VAR. AMPHORA CLEVE 



Valve asymmetrical, with the median line curved. Frustule sub-acute at the ends. 

 Median lines not on the same side of each valve of the frustule. 

 Abundant at Cape May, N. J. Not common elsewhere. 

 PL 14, Figs. 10 and 11. 



GOMPHONEIS CLEVE (1894) 

 (gomphos, a peg, and neis (naus)) 



Valve elongated, asymmetrical to the transverse axis; axial area narrow; central area 

 rounded, stigmatic; striae radiating, costae alternating with double rows of fine puncta. An 

 indistinct, longitudinal line near the border. 



Chromatophores and conjugation have not been determined. 



