SOME NORTH AMERICAN DESMIDIE.E. 257 



112. Staurastrum inconspicuum, Nordst. Bidrag Sydlig. Norges Desm p 26 t 1 

 %. 11. 



Long. 12-5-16 ^; lat. 11-2-15 ^t; lat. istlim. 6-65 ^i. 



We have met with this frequently in N. American s^atherings, and, as WoUe's figure is 

 somewhat crude, we give a figure of the front view of a rather broad form (long. 15-5 ft ; 

 lat. 17-8 n ; lat. isthm. 5'5 ^i). (PI. V. fig. 14.) 



113. S. Hantzschii, Reinsch, Spec. Alg. Pung. p. 129, t. 22 d. figs. 1, 1, 6. 



Var. CONGRUUM, nobis. (PL XVI. fig. 15.) (S. Benardl, Reinseli, var. congnmm, 



Racib. in Pamiet. Akad. Krak. xvii. (1890) p. 101, t. 3. fig. 11 ; S, Hanfzschn, 



Reinsch, var. depauperatum, Gutw. in Sprawozd. Akad. Krak. xxvii. ii. (1892) p. 71, 



t. 3. fig. 23 ; S. intricatum, Delp. (ex part.) Desm. Subalp. t. 11. fig. 15.) 



Long. s. proe. 335 fx, c. proc. 40 ^ ; lat. s. proc. 26 ^, c. proc. 36 /u ; lat. isthm. 13'5 /u. 



Hah. Scarbro', Maine. 



Several examples of this were observed ; they all had six short, thick processes, with 

 tridenticulate apices in the superior whorl, and nine similar ones in the inferior whorl. 

 The sides in the vertical view were slightly convex. This plant is evidently the one 

 seen by both Raciborski and Gutwinski, and is certainly a form of S. Hantzsohii, Reinsch, 

 and not of S. Henai^di, Reinsch ; as Raciborski's name is the earlier one, Ave liave 

 adopted it, 



114. S. QUADRicoiiNTJTiJM, Roy et Biss. in Journ. Bot. xxiv. (1886) p. 240, t. 268. fig. 4. 

 Long. c. proc. 27*4-30 n\ lat. c. proc. 25-28 ^i', lat. isthm. 8-8'7 ^l, 



This is not an unfrequent species. Roy and Bisset say that " it is in front view 

 entirely difi'erent from any other known species." S. gemellipariim^ Nordst. (in Vidcnsk. 

 Meddel. 1869 (1870) p. 230, t. 4. fig. 54), however, is very near it. 



One of the specimens seen had the two inferior processes of one angle replaced by a 

 single larger process. (PI. XVII I. fig. 18.) 



115. S. QUADRANGULARE, Breb. in Ralfs, Brit. Desm. p. 128, tab. 22. fig. 7. 

 Long. 20 |t; lat. s. spin. 25-30 ^, c. spin. 30-34 n ; lat. isthm. 13*5 /*. 



A broad form of this with somewhat longer spines is figured for comparison with the 

 following variety. (PL XVI. figs. 16, 17.) 



Var. ARMATUM, nov. var. (PL XVI. fig. 18.) Var. spinis ad angulos superiores longi- 

 oribus, lis ad angulos inferiores spinis bifurcatis cum cuspidibus inajqualibus 

 (cuspidibus longioribus prope basin). 

 Long. 22 ;» ; lat. s. spin. 25 ny c. spin. 32o ^i ; lat. isthm. 10*5 ^. 



All the specimens seen were triangular in vertical view. Compare with vV. mntectum, 

 W. B. Turn., and var. mevolutum, W. B. Turn. 



116. S. coNTECTUM, \\ . B. Tum. Ereshw. Alg. of E. India, p. Ill, t. 15. fig. 20. 



Var. iNEVOLUTUM, W. B. Turn. /. c. t. 15. tig. 2, & t. 27. fig. 11. (PL XVI. tig. 19.) 

 Long. 26-27 m ; lat. c. spin. 30-5-32'5 ^i ; lat. isthm. 7-7-5 /i. 



