rROCEEDINGS OF THE KATIOKAL MUSEUM. 525 



claAv ; the outer edge of the daetylus, a compound curve, and the median 

 carina of the carapace distinct in front. The lateral processes of the 

 sixth and seventh' thoracic segf men ts in S. e^npusa are acute, but hardly 

 acuminate, and the subraedian carina^ of the fourth and fifth abdominal 

 sejiments end in spines. The marginal spines of the telson are also not 

 unusually long, and on the ventral surface there is a distinct postanal 

 carina, or keel ; while the two joints of the exopodite of the uropod are of 

 equal length, and there is no lobe on the inner spine of the basal pro- 

 jection. 



The small female specimen from Panama, referred to above, occupies 

 an intermediate position between the larger sjiecimen I have just 

 described and S. cmpusa. The eyes are the same size as in the latter, 

 relatively to the length of tlie body, but the ratio of the length of the 

 peduncle to that of the corneal axis is greater than in ^S. empusa and 

 like that of the type si^ecimen. The outer edge of the raptorial dacty- 

 1ns is a compound curve and the dorsal surface and the margin of the 

 teLson closely resemble the condition found iu H. empu.sa., but in all 

 other respects this si^ecimeu agrees with the type. .Vs the females and 

 the young of both sexes are known to differ from tlie mature males in 

 several si^ecies of SqnlUa, I think it most probable that this small 

 specimen represents an immature condition of the larger one. 



Color. — The larger specimen has completely fiided, but the smaller 

 one has a symmetrical mottled arrangement of dark pigment cells. 



Size. — Length of body, 15 cm. and 6,85 cm. 



Locality. — The large specimen was collected by AV. II. Jones, XJ. S. 

 Navy, tlieii on board the U. S. S. Wachusett at Iquique, Chile (So. 11198, 

 U.S.N.M.). The snniller one was taken at Panama and was pur- 

 chased from n. A. Ward (Xo. 15020, 'IT.S.K.M.). 



SQTJILLA EMPX^SA. Say. 



Squilla empusa, Sav, Journ. Acad. Nat. Sci. Pliila., i, p. 250, 1818. — Milne- 

 Edwards, Hist. Nat. Crust., ii, p. 525, 1837. — Ue Kay, New York Favma, vi, 

 Crust., p. 32, 1844.— MiERS, Aun. and Mag. Nat. Hist. (5) v, p. 23, 1880.— 

 Brooks, Voyage of the Challenf/er, xvi, p. 25, 1886. 



Diagnosis. — Eyes triangular and with oblique corneal axis equal to 

 peduncular axis; six teeth on the dactylus of the raptorial claw, the 

 outer edge of the dactylus sinuate; rostrum variable, generally a little 

 longer than broad, subquadrate or hemiellipsoidal and possessing lat- 

 eral and median carina' ; carapace with five carinte, the median one 

 bifurcated, the lateral ones produced into large anterior lateral spines, 

 the posterior lateral margins angled; the fifth thoracic segment with 

 separate ventral and lateral spines, the latter being slightly curved for- 

 ward and acute; the lateral processes of the next two segments strongly 

 produced and acute or mucronate; eight carinte on the first five abdomi- 

 nal segments; telson witli crest and curved lines of pits, six marginal 

 spines and-eight basal carina/ and on each side three to four submedian, 



