PART 1 GARTH : PACIFIC OXYRHYNCH A 173 



free antennal segment cylindrical. Legs slender. Male first pleo- 



pod with a protective flap and row of papillae 



2a. Groove of maxilliped extending entire length of ischium; 

 merus not produced externally. No spine at anterolateral 

 angle of basal antennal article. Apertural flap of male first 

 pleopod rounded beneath lamellifrons 



2b. Groove of maxilliped occupying basal portion of ischium 

 only ; merus produced externally in a thin blade. A spine at 

 anteroexternal angle of basal antennal article. Apertural 

 flap of male first pleopod squarish . clarionensis, n. sp. 

 lb. Preorbital horns equaling or exceeding rostral. Width of pos- 

 terior medallion appreciably exceeding length. Ischium of 

 external maxilliped not grooved, inflated ; basal projection 

 of exognath posteriorly directed. First free antennal seg- 

 ment flattened. Legs robust. Protective flap of male first 

 pleopod rudimentary, row of papillae lacking 

 galapagensis, n. sp. 



Tyche lamellifrons Bell 

 Plate J, Fig. 4; Plate 18, Fig. 2 



Tyche lamellifrons Bell, 1835b, p. 173; 1836, p. 58, pi. 12, fig. 3, 3f-j. 

 Stimpson, 1871a, p. 97. A. Milne Edwards, 1878, p. 126. Bouvier, 

 1895, p. 8. Rathbun, 1898, p. 572; 1910, p. 573; 1925, p. 508, pi. 

 273, figs. 1-6. Crane, 1937, p. 64. Garth, 1948, p. 30. Buitendijk, 

 1950, p. 274. Not Garth, 1946, p. 406, pi. 54, figs. 1-6. 

 Tyche brevipostris [for brevirostris] Lockington, 1877c, p. 74; type 

 locality, Port [Puerto] Escondido, Gulf of California, Mexico; 

 female holotype not extant. 

 Type: Male holotype, length 14.8 mm, width 8.5 mm; not in British 

 Museum, as stated by Rathbun (1925), fide I. Gordon (personal com- 

 munication, March 12, 1956). 



Type locality: Panama; Hugh Cuming, collector. 

 Localities subsequently reported, with collectors: Lower California, 

 Mexico: L. Diguet (Bouvier) ; Cape San Lucas, J. Xantus (Stimp- 

 son). Gulf of California: Santa Inez Bay, 2.5-29 fathoms, Zaca 

 (Crane) ; Port [Puerto] Escondido, W. J. Fisher (Lockington, as 

 Tyche brevirostris) ; San Lorenzo Channel, 7 fathoms, Albatross (Rath- 

 bun, 1898). Mexican mainland: Acapulco, Guerrero, Exped. Escuela 

 Nacional de Ciencias Biologicas (Buitendijk). Ecuador: Off Esmeraldas, 

 9-27 meters, Askoy (Garth, 1948) ; not Galapagos Islands, 0-20 fath- 

 oms, Velero III (Garth, 1946). 



