46 FOSSIL CIRRIPEDIA. 
what appeared to be upper latera, but as I could not remove them so as to examine their 
under sides, I am far from sure that they were not broken, angular portions of scuta. If 
we look to the character of the separate valves, there is a striking and important resem- 
blance between the scuta of S. crete and tuberculatum, in the umbo being seated in a 
nearly middle point of the occludent margin, and likewise in the two ridges running from 
the umbo to the baso-lateral angle, and to a central pomt of the basal margin; in which 
latter character of the ridges, this species also agrees with S. semzporcatum. 'These facts 
have determined me, provisionally, to rank the present species under Scalpellum. But on 
the other hand, if we look to the carina, which, according to our rule, is considered the 
characteristic valve in this genus, it rather resembles the homologous valve in Pollicipes ; 
for the carina has not any parieties separated from the tectum by a distinct ridge. The 
terga seldom afford any serviceable generic characters; but as far as they go, they also 
rather resemble the terga in Pollicipes than in Scalpellum. Hence, it is obvious, that the 
generic position of S. (?) crete is at present very uncertain. 
Valves small, smooth, extremely thin and brittle. 
Scutum (fig. 11, c); trapezoidal, with the upper part of the valve produced into a sharp 
point, and with the rostral angle slightly and obliquely cut off. Umbo seated at a little 
above the middle of the occludent margin, which is straight. The tergal margin is longer 
than the lateral margin: the basal margin (on the carinal side of the truncated rostral end) 
forms a right angle both with the lateral and occludent margins. Valve somewhat convex 
near to the umbo, whence three obscure ridges radiate,—one to the angle between the tergal 
and lateral margins ; a second to the baso-lateral angle, and a third to the bend in the basal 
margin ; these ridges, however, seem to vary in strength, and in the largest specimens 
could hardly be distinguished: in most of the specimens, the narrow portion of the valve, 
which ends in the truncated rostral angle, is a little inflected. The lines of growth follow 
the basal and tergo-lateral margins, and can be traced just bending round the sharp 
apex, so that a very narrow ledge is added along the upper part of the occludent margin. 
Tergum (fig. 21, a); sub-rhomboidal, nearly flat: the carinal margin consists of an 
upper larger portion, and of a lower, shorter portion: the occludent and scutal margins 
are nearly equal in length. The apex is a little curled towards the scuta, and is sharp; 
basal angle bluntly pointed. A faint curved ridge runs from the apex to the basal angle, 
at about one fourth of the entire width of the valve from the carinal margin. 
The Carina (fig. 11, 6) widens rapidly downwards from the extremely sharp apex ; 
basal margin spear-shaped, sharply pointed, the two edges meeting each other at about an 
angle of 75°; exterior surface sub-carinated; in a transverse line the valve is slightly arched, 
and longitudinally, very slightly bowed inwards: with a lens, traces of longitudinal strize 
are visible. 
Dimensions. The species seems to have been always small: the largest scutum and 
tergum were each about a quarter of an inch in length. Probably the individuals were 
attached in groups to corallines at the bottom of the cretaceous sea. 
