420 PROCEEDINGS OF THE ACADEMY OF [1879. 



Genus Crypiiiops Dana. 1 Rostrum of medium size ; eyes wholly 

 hidden under the earapax, as in Alpheus ; external maxillipeds 

 slender. Type Gryphiops spinulosimanus Dana. 



Sub-Family Oplophorinae. 



First pair of pereiopoda either didactyle or vergiform, second 

 stouter, chelate; antennulae biflagellate. 



Genus Oplophorus M. Edw. Rostrum long, dentate, pereio- 

 poda all palpigerous ; four anterior chelate ; antennal scale with 

 the external margin spined ; abdomen armed above with one or 

 more long spiniform ])rocesses. Type Oplophorus typus M. Edw. 



Genus Caulurus Stm. 2 Rostrum long or short ; basal scale of 

 antennulae wanting : basal scale of antennae externally unarmed ; 

 external maxillipeds pediform, with exognath ;' pereiopoda fur- 

 nished with exopodite, the first two pairs chelate, the second pair 

 slender and long ; dorsum of abdomen unarmed ; sixth abdominal 

 segment long and slender. Type Caulurus pelagicus Stm. 



As there is nothing except the length of the rostrum to sepa- 

 rate Xi])hoca?'is from Caulurus, I have thought best to unite 

 them. Xiphocaris has but a single species, Hippolyte elonyata 

 Guerin = Oplophorus Americanus Saussure. 



Genus Thalassiocaris Stm. 3 Rostrum and antennulaa as in 

 Oplophorus. Feet not palpigerus, anterior pair not chelate ; se- 

 cond pair stout, chelate ; mandibular palpus triarticulate ; third 

 segment of abdomen prolonged into a long spine above. Type 

 Thalassiocaris lucidus (Dana, sp.). 



Family PEN^JIDiE. 



Genus Sicyonia Edw., Stm. 



Sicyonia laevigata Stm. A single specimen of this species 

 was collected at Sarasota Bay, Fla. 

 Sicyonia carinata M. Edw. 



Palcemon carinatus Olivier, Encyclopedic Methodique, viii. p. 667 (teste 

 Edw.). 



' Op. cit., p. 594. 



2 Proc. Acad. Nat. Sci. Philadelphia, 1860, p. 42. Xiphocaris, E. von 

 Martens, Archiv fur Naturgeschichte, xxxviii. Bd. i. p. 139 (1872). 



3 Proc. Acad. Nat. Sci. Philadelphia, 1860, p. 42. Regulus, Dana, op. 

 cit., p. 597 (nomen prseoccupatum). 



