213 



HAMITES (?) GLABER. (N. Sp.) 

 Plate 24, figs. 2, 2a, 26, and 2c. 



Shell, so far as known, consisting of two straight and parallel 

 limbs of nearly equal size, one of which is bent so closely on the other 

 that the inner surfaces of both are nearly or quite in contact. Sides 

 of both limbs compressed, so that the outline of a transverse section 

 of either would be elliptic ovate, the siphonal edge being slightly 

 narrower than the antisiphonal. Surface apparently smooth, but 

 marked at widely distant intervals by an occasional arrest of growth 

 in the shape of a broad, but faint and shallow, flexuous and transverse 

 constriction, which is obliquely ascending on the antisiphonal half of 

 the limb and nearly straight on the siphonal half. 



Each septum in its entire circumference consists of six bipartite 

 saddles and five bipartite lobes. The siphonal saddle is small and 

 simple, though its summit is minutely three-lobed and its sides thrice 

 incised. The three lateral saddles are nearly equal in size, but the 

 second is a little higher than the first, and the third than the second. 

 They are not at all alike in their ramifications, the second or central 

 saddle being twice bipartite and symmetrically or equally divided, while 

 the first and third saddles are unequally divided throughout, the largest 

 half in each case being that which is nearest to the second saddle. At 

 the base of each of the bipartite saddles there is a short incised spur or 

 offset from each side of the stem. Between the first and second and 

 between the second and third lateral saddles there is a small and 

 simple but laterally incised supplementary saddle, but there is none 

 between the siphonal saddle and the first lateral. 



The siphonal lobe is equally and twice bipartite. The first and second 

 lateral lobes, which are nearly equal in size and which are slightly 

 larger than the siphonal lobe and much larger than the antisiphonal, 

 are unequally divided throughout. The first lateral lobe is deeply but 

 unequally twice bipartite above, and its stem bears a pair of simple 

 incised branchlets in the middle. The second lateral lobe is deeply 

 divided into two branches of very unequal size, one of which is simply 

 cleft at the summit, while the other is again deeply divided into two 

 branchlets whose apices are also cleft. The antisiphonal lobe is strictly 

 symmetrical, its extremity being regularly trifurcate and the centre 

 of the stem deeply constricted. Alternating with each of the primary 

 and bipartite lobes there is a single but much smaller supplementary 

 lobule, which although incised is not branched. 



North Shore of Cumshewa Inlet : three well preserved but fragment- 

 ary casts, all of which are figured. 



