318 MESSRS. W. WEST AND G. 8. WEST ON 
There can be no doubt that S. leptocladum always possesses 
the two spines at the apex of the semicells; this was made the 
character for a variety (v. cornutum) by Wille, but we think it 
highly probable that these spines had been broken off in the 
specimens originally described by Nordstedt. All the examples 
we have ever seen of this species from many diverse parts of the 
world possessed these spines, and it is worthy of note that other 
observers record only the v. cornutum, a fact which confirms 
our suspicions 2s to the invariable presence of the apical spines 
in uninjured examples. 
158. SravrastruM Jounsonti, West 4 G. S. West, in Trans. 
Linn. Soc., Ser. Il. (Bot.), v. p. 266, pl. 17. f. 16. 
Hab. Cold Spring Harbour, N.Y. (H. J. no. 176). Ann. 
Arbor, Mich. (H. J. n. 312). Meredith and Holderness, N.H. 
Whitmoor Lake, Mich. Laconia, N.H. 
154. S. Axcnona, West & G. S. West, l. c. pl. 17. ff. 18-20. 
Long. 76 u; lat. 140 u. 
Hab. Laconia, N.H. (H. J. no. 657). 
153. S. Cerastes, Lund. ia Nov. Act. Soc. Scient. Ups. Ser. III. 
viii. no. ii. p. 69, t. 4. f. 6. 
Long. 56 u; lat, 64 p. 
Hab. De Land, Florida (H. J. no. 589). 
156. S. MACROCERTYM, Wolle, 1880; Desm. U. S. p. 134, pl. 48: 
ff. 3-5. 
Lat. c. proc. 150-165 p. 
Hab. De Land, Florida, occasional (H. J. no. 592). 
157. S. RADIANS, n. sp. (PI. 18. fig. 18.) . 
S. mediocre, pene duplo latius quam longum (cum processibus), 
modice constrictum ; semicellule obverse subsemicircularibus, apt- 
cibus subrectis glabrisque, angulis in processos validos horizontales 
productis, apicibus processuum tridentatis (ut visis); 4 vertice 
vise circulares processibus validis radiantibus 8, verruca emar- 
ginata ad basin processus uniuscujusque utrobique et denti 
duobus ad marginem unumquemque, apicibus processuum quadri 
dentatis; membrana glabra. | 
Long. 42 p; lat. 68-80 p ; lat. isthm. 21 p. 
Hal. De Land, Florida (H. J. no. 583). 
