NO. 2135. NEW PHILIPPINE CRABS— RAT II BUN. 547 



HYASTENUS SCROBICULATUS, new species. 



Type-locality. — Tawi Tawi Group, Sulu Archipelago: Tinakta 

 Island (K), S. 72° W., 2.75 miles; lat. 5° 12' 40" N.; long. 119^ 55' 

 10" E.; 12 fathoms; S.; Feb. 22, 1908; station 5160, Albatross. 



Holotype.— Male. Cat. No. 48218, U.S.N.M. 



Measurements. — Length of carapace on median line, 8.2; length 

 of rostral horns, 2; width of carapace, 5. 



The cardiac region is the highest part of the carapace; it is sur- 

 rounded by a trench and surmounted by a conical tubercle; a low 

 tubercle may be seen on the posterior slope. Four median gastric 

 tubercles, the second (from the front) very low, the others promi- 

 nent; either side of the second and at some distance there is another 

 tubercle; an arch of four spines or tubercles near the margin of the 

 branchial region ; the posterior one is a spine of fair size, the others 

 are pointed tubercles diminishing in size anteriorly; an intestinal 

 and a marginal hepatic tubercle ; a row of three subhepatic and sub- 

 branchial tubercles and a row of two pterygostomian tubercles. 

 Eostral horns flattened, regularly tapering, outer margins parallel. 

 Anterior angle of preorbital hood produced obliquely in a short 

 acute spine, posterior half of outer margin rounded and produced 

 strongly outward; orbital sinus narrow; postocular cup triangular. 

 Basal antennal segment wide and with two triangular, acute teeth 

 or spines directed obliquely forward. 



Chelipeds weak, no longer than carapace exclusive of rostrum; 

 palms rough above, fingers narrowly gaping at base. Legs very 

 slender, spinules of dactyli minute. 



Relatio7iship. — In the shape of carapace, details of orbit and basal 

 antennal segment and roughness of cheliped, this species resembles 

 H. hiformls (p. 545), but can at once be told by the isolated cardiac 

 region surmounted by one tubercle instead of two side by side, by 

 the four instead of two median gastric tubercles, and by the flat- 

 tened rostrum. 



HYASTENUS TINAKTENSIS. new species. 



Type-locality. — Tawi Tawi Group, Sulu Archipelago: Tinakta 

 Island (N.), N. 82° W., 1.4 miles; lat. 5° 11' 50" N.; long. 119° 54' 

 E.; 10 fathoms; Co. S.; Feb. 21, 1908; station 5159, Albatross. 



II olotype.— Female. Cat. No. 48221, U.S.N.M. 



Measurements. — Length of carapace in median line, excluding 

 spine, 11; length of rostral horns, 2.8; width of carapace without 

 spine, 7.3. 



Carapace wide, strongly constricted behind the spreading orbits; 

 surface strongly tuberculate and spinate: three blunt spines or high 



