] 78 CATALOGUE OF THE BLASTOIDEA. 



than other examples from the same locality do (PI. V. fig. 17). The ambulacra are 

 narrower, longer, and also straighter than in the Eifel specimens, while the summit 

 is also much more constricted (PL IV. figs. 17, 18 ; PL V. figs. 3, 4). Except in 

 the latter point it somewhat resembles P. Americana, Barris l ; but the radial sinuses 

 of this type are rather wide and their edges slope down towards the ambulacra as in 

 P. Lnsitanica (PL IV. figs. 11, 12), which is by no means the case in any forms of 

 P. clavata (PL IV. figs. 17, 18 ; PL V. figs. 3-5, 17). 



The figured specimen of this variety is a good deal weathered, and it shows how 

 the lancet-plate is completely covered by the side plates, and in its turn conceals the 

 hydrospires, which are fully visible at the distal end of the sinus, not being received 

 into the body of the radial, as is so often the case in Pentremites (PL V. figs. 3, 4) ; 

 while in fig. 5 the hydrospires are seen depending into the visceral cavity. 



Locality and Horizon. Colle, near Sabero, in the Province of Leon, Spain: 

 Calcaire d'Arnao, Lower Devonian. (Presented by Dr. P. H. Carpenter, F.R.S.) 



Pentremitidea Wachsmuthi, sp. nov. 

 (PL V. figs. 6-8.) 



Sp. Char. Calyx bud-like, or oblong-clavate ; summit convex, but contracted 

 and narrow ; peristome concave ; base short and triangular ; section somewhat 

 roundly pentagonal, the sides becoming gently concave about the basiradial suture ; 

 periphery equatorial, or perhaps a little nearer the base. Basal plates angular, 

 acutely so below, forming a short trihedral cup ; interbasal sutures on the flat 

 sides, neither on prominences nor in depressions. Radial plates oblong, nearly 

 parallel-sided ; bodies small ; limbs narrow, four times as long as the bodies ; sinuses 

 very long and narrow, with rim-like margins, arching closely downwards ; lips 

 moderately prominent ; radial angle 92°. Deltoid plates very small, horizontal, or 

 inclined inwards towards the peristome, but sometimes just visible in a side view. 

 Ambulacra moderately narrow, not inflated, nor arching outwards from the sides of 

 the calyx, but appressed to the latter, and depressed below the edges of the sinuses ; 

 side plates thirty and probably more ; ambulacral grooves broad and shallow at their 

 proximal ends. Hydrospires unknown ; spiracles large and oval, closely situated 

 around the mouth, and occupying by far the larger portion of the deltoid plates. 

 Mouth small. Column and ornament unknown. 



Remarks. This is a peculiar and well-defined species and may be at once recognized 

 by the short base, with the long and closely appressed ambulacra, which impart to the 

 calyx a very bud-like appearance (PI. V. fig. 6). It is clearly related to the group 

 represented by Pentremitidea acutangula, Schultze, sp., but is distinguished from it 

 by the shortness and the more vertical position of the bodies of the radials. In fact, 



1 Report Geol. Survey Illinois, 1883, vol. vii. p. 3(53; and Proc. Davenport Acad. Nat. Sci. 1S85, vol. iv. 

 p. 93, pi. i. Bg. 1. 



