54 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 89 



are obviously congeneric with P. crcscoitis, and in comparison with 

 the paratype specimens of Trcscolohus gramdofrons Chamberhn no 

 specific differences whatever were discovered. As the description of 

 this latter species outranks Domini codesmus geopkilus in time of 

 publication, the Haitian species must now stand as Psochodesmus 

 gramdofrons (Chamberlin). The following generic notes were made 

 from specimens of the Florida and Haitian species : 



Head with the granular area of the vertex traversed by a dis- 

 tinct median furrow. First segment somewhat flattened, much less 

 strongly convex than the next segment and with the margin and 

 lateral angles notably higher than the keels of that segment. Seg- 

 ments 2, 3, and 4 slightly shorter at the middle than segment 5. As 

 viewed from the side the keels of the segments do not reach below 

 the ventral third of the body. Anal valves distinctly convex and with 

 thin, raised margins. Sterna narrower than the diameter of the basal 

 joint of the leg on either side and with a definite median groove. 



Inasmuch as the original description of P. crescentis is extremely 

 brief, the following characterization has been prepared in order to 

 place it on a comparable basis with the other species. 



PSOCHODESMUS CRESCENTIS Cook 



Psochodesmus crescentis Cook, Brandtia, p. 25, 1896. 



Numerous specimens with 19 segments were collected between 

 Crescent City and Palatka, Florida, May 16, 1927, by O. F. Cook. 

 One 20-segmented male and three females were collected at Vero 

 Beach, Florida, April 22, 1933, by H. F. Loomis. Other specimens 



Fig. 27. — Psochodesmus crescentis. a, first segment, dorsal view; b, keels of 

 segments 9 and 10, dorsal view. 



have been collected at the United States Plant Introduction Garden, 

 Coconut Grove, Florida, by O. F. Cook and H. F. Loomis. 



First segment with the scalloped anterior margin broadly rounded, 

 the scallops short and broad, not separated by incisions (fig. 27, a) ; 

 surface with numerous small indistinct granules and two transverse 

 rows of round tubercles, four in the anterior row and six in the pos- 

 terior row. 



