106 BULLETIN 103, UNITED STATES NATIONAL MUSEUM. 



ENCOPE ANNECTANS Jackson. 



Plate 49, figs. 1, 2 ; plate 50, fig. 1. 



Encope annectans Jackson, Proc. U. S. Nat. Mus., vol. 53, 1917, p. 491, text 

 fig. 1 ; pi. 65, figs. 1, 2 ; pi. 66, fig. 1. 



This interesting species is represented by three specimens which 

 include two tests free from matrix and more or less complete, and 

 a sandstone mould of the exterior of the ventral side of a specimen, 

 which is the largest of the three. 



Fig. 1. — Encope annectans. Drawing of the type-specimen, natural size. Restored' 

 parts are indicated by dotted lines. 



In shape, the specimens are thin, flattened, and nearly circular in 

 outline, excepting for the reentrant marginal ambulacral notches. 

 The edges are thin, exceptionally so for the genus, and the whole 

 test superficially is scutelliform. In the anterior ambulacrum III 

 there is a shallow rounded notch, and in the lateral ambulacra are 

 deeper and narrower notches, the deepest being in the posterior pair 

 of ambulacra, IV and V. The apical disk is central. The peristome 

 is small and also central. Continuing posteriorly from the peri- 

 stome on the ventral side is a quite deep groove, and on the dorsal 

 side is a shorter and shallower groove. These grooves do not form 

 a hole through the test, but represent the incipient beginnings of the 



