FROM NEW YORK, NEW JERSEY, AND GEORGIA. 141 



N. TUBULOSA, Penard: 



Not abundant ; at Good Ground the large proportion of quadrangular 

 plates often present in the tests was a noticeable feature. 



Length 174-196 /* ; breadth 74-93 fj. ; aperture 30-35 jx. 



At Lakehurst an abnormally large individual occurred, length 300 //-, 

 breadth 150//., aperture 40 /i, the test principally composed of imbricated 

 discs 6-12 yu, in diameter ; it may have been a case of plastogomy or double 

 encystment. 



N. viTRiEA, Penard. (PI. 12. figs. 15-17.) 



Two individuals of large size similar to those^ until now, known only from 

 the deep Swiss Lakes, were found at Lakehurst.; length 258 /x and 187 /i, 

 breadth 135 fi and 130 /*, apertures 45 fx and 40 /j, ; they had tests com- 

 posed of square and angular plates, with apertures bordered by 8 or 9 large 

 grains. 



The form usually found at Lakehurst is smaller, often with a curiously 

 constructed test (figs. 15-17), in which circular plates predominate mixed 

 with some angular or irregularly shaped plates, the interstices between them 

 being re-enforced by small covering-plates somewhat similar to those figured 

 by Penard (36. p. 272, fig. 4), and analogous to the ones found on the test of 

 M. scutellata. 



Length 115-155 /* ; breadth 70-100 jjl ; aperture 23-31 fi. 



The small sphagnum-inhabiting variety of normal type and about 100 yu, 

 in length, as illustrated by Cash & Hopkinson (10), is not common in the 

 localities under investigation. As has been pointed out by Penard (45. p. 51 

 note), this form is intermediate in character between N. vifrcea, sp. ver., and 

 A^. dentistoma, but further investigation and comparison of specimens from 

 various localities are necessary in order to determine the limits of the various 

 forms ; they can be grouped, however, in a series of types which may be 

 differentiated as JS\ vitrcm, sp. ver., var. minor and var. sphagni ; all of which 

 occur in association at Lakehurst. 



Genus Quadrula, F. E. Sclmlze. 



QUADRULA SYMMETRICA ( WalUcJi), F. E. Sch. (PI. 12. figs. 18 & 19.) 

 Leidy, pi. 24. figs. 20-24 and p. 144 (30). 



This species is certainly very distinct from Q. irregularis (vide Penard, 39), 

 and approaches the genus Nehela \qyj closely, a relationship which is accen- 

 tuated by a comparison with such species as N. tropica and N. scutellata. 



Length 68-120 m ; breadth 45-74 /* ; aperture 20-30 /*. 



