COLLECTED BY CAPTAIN TOYNBEE. 189 



HAloctpeis rostrata, n. s. Superne visa elliptica, postice subaeuta ; latere visa literas 

 D formli similis, dorso fere recto, antice rostrato, postice rotundato. Antennae anticte 

 setis insequis. Spiculum eylindricum, antenna vix longins. Antennse posticte 7-ar- 

 ticulatge, articulo secnndo duplo longiore quam ultimi simnl sumti. 



This species is nearly allied to S. hrevirostrls ; and as my specimens wei'e mostly rather 

 smaller and the two were taken together, I was at first somewhat doubtful whether the 

 differences did not depend on age. The second segment of the posterior antennae is, how- 

 ever, longer in proportion to the terminal portion — a difference which Prof. Dana considers 

 of specific value (' Crustacea,' pp. 1302, 1303). Moreover some of the notched specimens 

 were as large as S. brevirostris. The setce belonging to the longer branch of the posterior 

 antennte are plumose ; those of the two-jointed appendage are naked. 



There is an indication of a minute segment at the base of the long branch ; and the 

 terminal portion also seemed to consist of six segments rather than five. 



The spiculum is scarcely longer than the anterior antenna. 



The three terminal segments of the maoidibular palpus scarcely diminish at all in 

 breadth. The second segment is short and broad. 



The two valves are similar to one another in outline. 



The shell is latticed by longitudinal and transverse bars. 



Length -g^th of an inch. 



Collected April 22, in S. lat. 0° 40', W. long. 0° 20'. 

 Pl. XXIX. fig. 33, X 30 ; fig. 34. mandible, x 30. 



HAiiOCTPRis ToTNBEEAisfA, n. s. Superne visa, brevissime ovata ; latere visa subrotun- 

 data, literse D forma similis, dorso fere recto, angulis rotundatis, fronte obsolete 

 prominula. Antennae anticae 3-articulatse, setis nudis, uno longiore. Antennae posticae 

 Q-articulatae, articulo secundo plus duplo longiore quam sequentes simul sumti. 



I have done myself the pleasure of calling this species after Capt. Toynbee, to whose 

 iadustry and love for science we owe this valuable collection. It differs from H. wfiata 

 in general outline, and in the posterior antennae. These latter are unlike those of any 

 other species, in the arrangement and form of the large hairs belonging to the little ap- 

 pendage ; these are six in number : four of them are simple and naked ; one is longer, 

 and clubbed at the end ; and the other is thick, and bent upon itself in the form of a sickle. 

 The larger branch of the antenna is 8-jointed, and the hairs belonging to it are plumose. 



The mandibles are like those of S. inflata in form, but differ a little in the arrangement 

 of the hairs. 



The two pairs of maxillae and of legs offer no very striking peculiarities. 



Length -rsth of inch. The animals were very active. 

 Collected June 25, in S. lat. 0° 40', W. long. 0° 20'. 



A collection made in N. lat. 7° 15', W. long. 27° 52', contained some specimens agreeing 

 very closely with this species, except in wanting the recurved spine on the appendage of 

 the second pair of antennae. This may perhaps be a sexual difference. 



Pl. XXIX. fig. 35, x 30 ; fig. 36. anterior antenna, x 30 ; fig. 37. posterior antenna, x 30 ; fig. 38. man- 

 dible, X 30 ; fig. 39. carapace, x 30. 



VOL. XXIII. 2 C 



