22 



BULLETIlSr 93, UNITED STATES NATIONAL MUSEUM. 



smooth; their basal borders are broadly inflexed (fig. 2). Both mov- 

 able valves have three yerj low, flat ribs. 



The movable scutum has the usual crescentic rib, a broad, flat, 

 strongly projectmg median articular rib, another very narrow one 

 above it, the rest of the plate having well-spaced, narrow, transverse 

 grooves. Inside there is a deep, oblique articular furrow near the 

 apex, receiving the upper articular ridge of the tergum. This is 

 bounded inside by a short, high ridge back of which is the rather deep 

 pit of the scutal adductor muscle. Nearer the basal edge there are 

 several low callous lumps, variable in form and position (fig. 5.) 



The movable tergum has a deep recess in the middle of the scutal 

 border, at the termination of a median articular rib; above this there 

 is a flat, wide upper articular rib, and below it a narrow diagonal 

 rib. The rest of the plate is transversely grooved. The internal 

 face (fig. 5) is nearly flat. 



The fixed scutum has only faint sculpture of growth lines outside, 

 or sometimes the triangular area next the occludent edge is vertically 

 grooved. The beak is not produced, but lies in close proximity to 

 that of the movable scutum. From the inside wall a prominent 

 semicircular adductor ridge or myophore depends, concave on its 

 upper face (fig. 3.) Externally, there is a very small radius in the 

 tergaj suture; below a small ala on the fixed tergum. 



The fixed tergum is about as large as the fixed scutum and similarly 

 sculptured. 



The carina and rostrum articulate by a suture weakly zigzag 

 below, but the carina has one large tooth above, between two smaller 



1 Some material preserved dry was labeled as from Albatross stations 2662-3, 2669, 2671-2. Among other 

 organisms it contained fragments of coral and more or less perfect examples of tlie following Cirripedia: 

 Scalpcllum longicarinatum Pilsbry. 

 Calaniica siipcrba (Pilsbry). 

 Verruca coralioplnla rUsbry. 

 Hexelasma amcrkanum Pilsbry. 

 These stations are situated as follows: 



U.S. F.G. Station. 



Latitude 

 north. 



Longitude 

 west. 



Depth in 

 fathoms. 



Bottom 

 tempera- 

 ture. 



2662 

 2663 

 2669 

 2671 

 2672 



29 24 30 



29 39 00 



31 09 00 



31 20 00 



31 31 00 



79 43 00 



79 49 00 



79 33 30 



72 22 00 



79 05 00 



434 

 421 

 352 

 280 

 277 



43.7 

 42.7 

 43.7 



54.3 



Coral was reported from stations 2609 and 2671. Material preserved wot from station 2009 contained the 

 typesof Calantkasupcrba; the typo of Hexelasma americanum is from station 2003; and thatof ,':>cal/Hilum 

 lonykarinaium Ls from station 2068. It is therefore impossible to draw any inference as to the part icnlar sta- 

 tion or stations which supnlied tlie barnacles of this mixed lot, but this is not of great importance suico all of 

 the stations m question are in the same district, and except the last two they do not differ much in depth 

 or temperature. 



