374 BULLETIN 129^ UNITED STATES NATIONAL MUSEUM 



PITHO DISPAR, new species 



Plate 132, fig. 1; plate 133, fig. 1 



fOlhonia quinquedentala Aurivillius (not Bell), K. Svenska Vetensk.-Akad. 



Handl., vol. 23, 1889, p. 56, pi. 3, fig. 9 (Wreck Bay, St. Thomas). 

 Pitho anisodon Rathbun, Bull. U. S. Fish Coram., vol. 20, for 1900, pt. 2 



(1901), p. 77 (part: specimen from Culebra). 



Type-locality. — Ensenada Honda, Culebra Island, Porto Rico; 

 1 ovigerous female, holotype. (Cat. No. 24205, U.S.N.M.) 



Diagnosis. — Four lateral teeth. Rostral lobes rounded, riot 

 pointed. Orbital lobes not produced. Lobe of first movable 

 segment of antenna small. 



Description. — Carapace longer than wide, oblong-oval and hairy; 

 branchial regions sparingly granulate; lateral teeth four, of rather 

 small size, the first or anterior tooth low, its sides at right angles to 

 each other, end rounded; three remaining teeth broad, curved, with 

 a short, sharp point, the second tooth widest, the third most out- 

 standing; in the interval between the first and second teeth of the 

 left side there is a small tubercle. Rostrum divided into two short, 

 rounded lobes or teeth. Orbital angles not produced, inconspicuous, 



Fig. 119.— Pitho dispar, female (24205), outline of front and orbits, from below, X 6. 



anterior margin of preorbital lobe and of basal antennal segment 

 transverse, not oblique as in other species; postorbital lobes with 

 outer margins converging anteriorly, terminal angle a right angle. 

 First movable segment of antenna narrow, a little longer than wide, 

 outer lobe short, directed forward. 



Variation. — Only two specimens of the species have been ob- 

 served. The second one is also female, but immature -and smaller 

 than the holotype, and differs from it as follows : The branchial granu- 

 lation is scarcely visible; the second lateral teeth lack a sharp tip, 

 and may perhaps be broken off; there is no trace of a tubercle between 

 first two teeth; the rostral lobes, though very short, are very obtuse- 

 angled; the anterior margin of the pre-orbital lobe is slightly oblique; 

 the outer margins of the postorbital lobes are subparallel. 



Measurements. — Female, holotype, entire length of carapace 17.3, 

 entire width 15.7, width without lateral teeth 14.6, fron to-orbital 

 width 8.6 mm. 



Range. — St. Thomas; Porto Rico. 



Material examined. — 



St. Thomas; 1884; Albatross; 1 young female (16189). 



