64 BULLETIN" 16 5, UNITED STATES NATIONAL MUSEUM 



mation of the peripores both on the genotype S. verruculosus as well 

 as on S. compositus, although he has indicated them on his figures 

 1 and 3. The zooecia that he figured are either worn or have an in- 

 completely formed frontal. In reality the frontal is covered by 3 

 or 4 transverse rows of salient peripores, their growth corresponding 

 to the lacunae, as one can see on our figure. The zooecia thus orna- 

 mented are the commoner ; the others are rare. 



All the apertural armature is more or less salient, forming thus 

 a sort of peristomie. When it is not salient, the distal peristome 

 (the distal shield of Lang) appears to be solid; but if it is salient 

 the three distal fenestrae indicated on S. vewuculosus and on 

 /S. ordinatus, appear distinctly at the base of the armature upon 

 inclining the preparation. A curious consequence of this variation 

 is that the peristomice and the apertura have an identical form. 



The formation of frontal peripores is a phenomenon not rare in 

 the Cribrimorphs. We have noted it in the genus Acanthocella 

 Canu and Bassler, 1917, in Cribrilina vem^ucosa Canu and Bassler, 

 1920, of the Midwayan, and it has been known for a long time on 

 the Cribrilina cryptoecium Norman, 1903, of Eecent seas. We still 

 do not understand their significance, and Lang himself does not 

 discuss them. 



On jS. compositus, the proximal shield, that is, the proximal por- 

 tion of the peristomice, is not developed. It varies a great deal 

 according to the species and even among the zooecia of the same 

 specimen. 



Occurrence. — Vincentown limesand: Very rare near Blackwoods- 

 town and at Vincentown, N.J. 



Plesiotypes.— U.S.N.M. No. 73911. 



STICHOCADOS MUCRONATUS, new species 



Plate 13, Figure 8 



Description. — The zoarium is encrusting. The zooecia are dis- 

 tinct, separated by a deep furrow, little elongated, oval or clavi- 

 form; the frontal is convex and formed of 8 to 10 costules almost 

 entirely joined together and separated only in their proximal por- 

 tion by a large lacuna; the proximal shield is formed by the much 

 thickened apertural bar, salient, bearing a large salient mucron, 

 covering in part the apertura; the distal shield is formed by the 

 more or less complete fusion of 4 distal spines placed above the 

 avicularia and more or less united laterally to the proximal shield. 

 The apertura is semicircular with a straight proximal border. On 

 each side of the apertura there is a small triangular avicularium with 

 a pivot, arranged almost transversely; the beak is very pointed and 

 oriented toward the center of the apertura. The ovicell is hyper- 



