NUCULA (CUCULLELLA ?) PAL^STINA. 55 



Nucula (Cucullella?) Palaestina, sp. uov. 



Plate VI, figs. 5 a-i. 



Testa parva, subcjjlindrata, duplo loncjior qumn altior, maxime incequilatera et 

 ventricosa, crassiiiido cdtitudini fere adceqiians ; antice attenuata snbmucronata ; extre- 

 mitas posiica paulo comprcssa, acuta ; margo dorsi antice insirmata, postice puididaimi 

 decUvis ; margo veniris antice sitbsimiata, postice cequaliter arcuata : imibones humilcs 

 inconspicui, antrorsimi inclinati: lunida siiperne angido aciito apicuni definita, inferne 

 vix Uniitata : superficies striis concentricis tenuibus confertissimis notata : cardo mul- 

 tidenticidatits ; linea cardinalis obtusangida. 



vSliell small, subcylindrical, twice as long as high, exceedingly inequilat- 

 eral and ventricose, the thickness almost equalling the height; atteniiate 

 and submucronate in front ; hinder extremity a little compressed, sharp ; 

 dorsal margin sinuated before, behind very gradually sloping; ventral margin 

 subsinuate in front, posteriorly regularly arcuated : umbones low, inconspicu- 

 ous, inclined forward : lunule defined above by the acute angle formed by the 

 beaks, below scarcely limited : surface marked by delicate concentric stride, 

 very closely set; hinge multidenticulate ; hinge-line obtusely angled. 



Thirty-three specimens, all with test entire. Length, 13 to lo| mm. ; 

 height, 7^ to 8^ mm. ; thickness, 7 to 8^^ mm. 



Of the whole number only a single specimen allowed the test to be 

 removed, leaving the cast with all its markings distinct, except the anterior 

 slope of the hinge line, which is partially obscured, but evidently toothed. 

 The muscular impressions are shown to be deep and somewhat angular, the 

 pallial line simple and rather distant from the ventral margin. The anterior 

 boundary of the umbones is more conspicuously angular and prolonged in 

 the cast than in specimens covered by the test. A little behind the beaks 

 of the cast a groove runs from the dorsal margin almost vertically downward 

 (slightly backward) about 2 nun. It is divided lengthwise into two grooves 

 by a ridge along its middle. In Cucidldla M-Coy,* according to the diagnosis, 

 " a strong internal septum [clavicle] extends from before the beaks to the 

 posterior margin of the anterior adductor, forming a deep slit in the casts." 

 Oar cast indicates the existence of a channelled septum (within the test) 



* Ziltel (Haudbiicb dcr Palseontologic, I. Baud, 2. Abtlieilung, p. 53) regards Cucullella M'Coy (Aunals 

 and Magazine of Natural History [2], VII, p. 50, 1851) and Cleidophorus Hull (Palaeontology of New York, 

 I, p. 300, 1847) as identical. Both are palaeozoic. 



