386 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 5 



Subfamily MaJINAE 



Genus THOE Bell, 1835 



Thoe erosa Bell 



Thoe erosa Bell, Proc. Zool. Soc. London, vol. 3, p. 171, 1835; Trans. 

 Zool. Soc, London, vol. 2, p. 48, pi. 9, figs. 4, 4k:-o, 1836. Rathbun, 

 Bull. 129, U.S. Nat. Mus., p. 351, pi. 249, figs. 1-6 and synonymy, 

 1925. 



Type locality. — Galapagos Islands, 7 fms, sandy mud. 



Type. — Not extant. 



Range. — Bay of Santa Elena, Ecuador (Nobili) ; Galapagos Islands 

 (Bell). 



Diagnosis. — Carapace depressed, posteriorly and laterally rounded, 

 tuberculous. Rostrum minute, bifurcate. Only one anterior lobe on basal 

 antennal article. Both rows of rectangular excavations on merus of che- 

 liped fully developed. Fingers slender and widely gaping; a single tooth 

 at basal third of movable finger. 



Material examined. — None. 



Remarks. — Judging from the writer's experience in collecting Thoe 

 sulcata Stimpson at Socorro Island, Mexico, and in collecting T. pana- 

 mensis Nobili on the mainland from Costa Rica to Gorgona Island, 

 Colombia, T. erosa would most probably be encountered among sponge- 

 covered rocks at extreme low tide. Since the type of collecting which 

 yielded the two former species was the type most frequently pursued by 

 Velero III collectors in the Galapagos Islands, it is difficult to understand 

 why the Bell species, if present, was not uncovered. 



Genus PITHO Bell, 1835 

 Key to the Galapagos Species of the Genus Pitho 



A^ Five anterolateral teeth, the second and third united at bases 



P. quinquedentata 



A^ Six acute anterolateral teeth, the second and third separated at 



bases P. sexdentata 



Pitho quinquedentata Bell 



Pitho quinquedentata Bell, Proc. Zool. Soc. London, vol. 3, p. 172, 1835. 



Rathbun, Bull. 129, U.S. Nat. Mus., p. 361, pi. 250, figs. 1-4, and 



synonymy, 1925. 



Type locality. — Galapagos Islands, sandy mud, 6 fms. 

 Type. — Not extant. 



Range. — Panama (A. Milne Edwards) ; Galapagos Islands (Bell). 

 Atlantic analogue. — P. Iherminieri (Schramm). 



