rments. 3 I segments have only two pairs of spines ai the anterior margin one pair 



ven long near the extremity and .1 second shorter pair about the middle ol its length. 



iudal appendages verj minute, one-jointed with a few spines near the extremity 

 and a short and feeble claw-like spine at the tip. 

 No penis. 



l'li, formed a single cluster in the specimen I opened; the) had a much more 



ngated shape than in several other species of Scalpellum. They measured 0,47 X 0,27 mm., 

 their number being 1 7. 



This specimen was furnished with .1 dwarf male at one side only. The latter was attached 

 t<> the inner surface ol the scutum near the occludent margin. Its shape was pear-like, the 

 luncular pole being considerably the narrower. It showed no tracé of valves. The prehensile 

 antennae were inserted very near the peduncular extremity. lts si/c was 0,5X0,3 mm. 

 The "Siboga" collected this interesting little species at: 



St.it. 241. December i, [899. Lat. 4 24.3 S., Long. [29 |-9'.3 E. Depth 1570111. Bottom: dark 

 -~.m<l with smal! stones. 



Observation. This species is very nearly related to Sc. balanoides Hoek collected 

 during the cruis.- of the " Challenger" at Lat. 5 42'S., and Long. [32°25'E. at a depth of 

 [29 fathoms, about 230 m. The latter species lias about the same size and lives attached to 

 the arms of Metacrinus Murrayi. Sc. sessile differs from it, 1" by the trapezoid nol triangular 

 m ut' its upper latus; 2 by the greater breadth of its infra-median latus; V by the form of 

 its carinal latus, which in Sc. balanoides has the apex, where the umbo is, produced and even 

 slightly recurved; and 4" by the shape of the carina, which is much more strongly bowed in 

 Sc. sessile than it is in Sc. balanoides. Perhaps on closer examination of the "Challenger" form at 

 least some of these differences might turn out to be not so important as 1 must consider them now. 



[8. Scalpellum ciliatum n. sp. PI. VII, fig. 17. 



Valves fourteen, covered by membrane, clothed with very long hairs. Carina simply bowed, 

 no flat roof. Tergum very large. Valves of the lower whorl small. Upper latus indistinctly 



quadrangular. Rostrum small, triangular. 



This very small species is represented by a single specimen only. 



The capitulum elongated, with the apices of the tergum and scutum produced. The 

 hairs which clothe the membrane are longest along the carinal margin of the capitulum. 



The scutum is elongated. quadrilateral, more than twice as long as broad, with the 

 upper part produced and pointed. 



The tergum is large, elongated rhomboid; the umbo is at the apex which is bluntly 

 pointed and not produci 



The uppermost (umbonic paris of scutum and tergum are naked, not covered by membrane. 



The carina is simply bowed longitudinally and also laterally. It reaches to about half 

 the length of the carinal margin of the tergum. 



The upper latus has the scutal margin parallel to the occludent margin ol the scutum 

 and it-- is not produced. The carinal and basal margins form together an arch. 



90 



