Ficure 52.—a, Pycnogonum littorale (Str6m); b, P. crassirostre Sars; c-f, P. reticulatum, 
new species: c, dorsal view of holotype; d, dorsal view of female specimen; e¢, oviger of 
holotype; f, leg of holotype. 
tions from the West Indies. On the eastern shore of the Atlantic it 
occurs as far south as Morocco. 
Schimkewitsch suggested that Pycnogonum stearnsi, the common 
Pycnogonum of the Pacific coast of North America from Alaska to 
San Diego, might be a variety of P. littorale. His reasons were based 
on Cole’s (1904a, p. 294) comparative table of differences between the 
two species. Schimkewitsch considered these differences secondary 
and suggested that transitional types might be expected in a large 
series. 
While I do not pretend that the comparative material at my dis- 
posal is extensive (58 specimens of P. littorale and 25-30 specimens of 
P. stearnsi), I have noticed no such transitional types. Aside from 
the considerable difference in size, the most consistent difference be- 
tween the two species is the shape of the proboscis. This always has 
the appearance of a flat ellipse from above in P. stearnsi, never the 
downward-pointing funnel shape which is characteristic of P. littorale. 
Bouvier mentions no pronounced variation in the shape of the pro- 
boscis in a series of 2,307 specimens of P. littorale he examined. 
