576 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxi. 



peds present no distinctive characters. The ambulatory legs are most 

 like those of bicarinata in having only one crest, the posterior, on the 

 carpus of the first three pairs of ambulatory legs, the anterior crest of 

 tiibcrosa being represented by a tooth. 



Dimensions. — Male: Length, 12.5 mm.; width, 13 mm. Immature 

 female: Length, 9.8 mm.; width, 10 mm. 



Type.— 1^0. 21575, U.iS.N.M. One male from ofl" Cape St. Lucas, 31 

 fathoms, station 2829. 



Additional specimen. — An immature female was taken in Magdalena 

 Bay, 12 fathoms, station 2831. 



This species resembles L. bicarinata, and differs from L. tuberosa in 

 its narrow ridges and in the single crest of the carpus of the ambula- 

 tory legs. It differs from both in its greater width and in the outline 

 of the posterolateral margin. 



30. LEPTOPISA SETIROSTRIS Stimpson. 



Tiarinia sefirostris Stimpson, Bull. Mns. Comp. Zool., 1871, II, p. 114. 

 Leptojnsa setirosiris .Stimpson, Bull. Mus. Comp Zool.. 1871, II, p. 114, in text. 

 Macrocwloma ienuirosira Rathbin, Proc. U. 8 Nat. Mus , 1892, XV, p. 252, pi. 

 XXXIII, fig. 1. 



Off" Cape St. Roque, Brazil, 20 fathoms, station 2758. 



31. MACROCCELOMA TRISPINOSUM (Latreille). 



Pisa trispinosa Latreille, Encyc. Mdth., Hist. Nat., Entoni,, 1825, X, p. 142. 

 Macrocwloma Irispinosa Mieks, Jour. Linii. Soc. London, 1879, XIV, p. 665. 



Port Castries, St. Lucia. 



32. MACROCCELOMA DIACANTHUM (A. Milne-Edwards). 



Pericera dicantha A. Milne-Edwakds, Crust. Reg. Mex , 1875, p. 57 (dicantha), 



pi. XV, fig. 3 {diacantha). 

 Macrocwloma diacantha MiERS, Jour. Linn. Soc. London, 1879, XIV, p. 665. 



Off" Cai^e St. Roque, Brazil, 20 fathoms, station 2758. 



33. MACROCCELOMA HEPTACANTHUM (Bell). 



Pericera Ueptacantha Bell, Proc. Zool. Soc. London, 1835, III, p. 173; Trans. Zool. 



Soc. Loudon, 1836, II, p. 61, pi. xil, fig. 6. 

 Macrocwloma hcptacantlia Miers, Challenger Rept., Zool., 1886, XVII, pp. 79, 81. 



Panama Bay, 18 fathoms, station 2798; off" Cape St. Lucas, 31 

 fathoms, station 2829. 



34. MACROCCELOMA CONCAVUM Miers. 



Macrocwloma concara Miers, Challenger Rept., Zool., 1886, XVII, p. 81, pi. x, 

 fig. 2. 



Off" Cape St. Roque, Brazil, 20 fathoms, station 2758, one female, 

 intermediate between the type as figured by Miers and the specimen 



