308 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 8 



Clypeaster speciosus Verrill 

 Plate 48, Fig. 29 



Clypeaster Speciosus Verrill, 1870a, p. 95. 



H. L. Clark, 1914, p. 31, pi. 135, figs. 1, 2; pi. 

 136, fig. 5. 



This is the common Clypeaster of the Gulf of California and the 

 Velero collection contains 143 examples of it, ranging in size from young 

 ones (6-20 mm long) whose specific identity may perhaps be debatable, 

 to full grown adults 120-130 mm long. The width is usually about 90 per 

 cent of the length, but shows considerable diversity ranging from 87 to 

 95 per cent. The color seems to be very constantly dark purple approach- 

 ing black ; but very young specimens are reddish violet, and orally lighter 

 than on the upper side. The resemblance to the preceding species has been 

 discussed above so that little need be said here, but it may be again emphas- 

 sized that the line between the two species is often invisible. 



Distribution. — This Clypeaster is pre-eminently characteristic of the 

 Gulf of California and the Velero has not found it anywhere outside the 

 Gulf save at Socorro Island, where a fine series of specimens was secured, 

 and at Clarion Island, where two adults and a half a dozen young 

 Clypeasters were taken which may well be referred to speciosus for the 

 present. As far north in the Gulf as collecting was done this Clypeaster 

 occurs, but south of the Gulf, it is apparently replaced by the preceding 

 species. 



Type. — Peabody Museum, Yale University. "None designated as 

 type." (Stanley C. Ball) 



Type locality. — La Paz, Gulf of California. 



Depth. — Shore to 50 fms. 



Specimens examined. — 143 specimens from 20 stations. 



Clypeaster elongatus*^, new species 

 Plate 48, Fig. 30; Plate 49, Fig. 31 ; Plate 50, Fig. 33 



Length 1 1 1 mm, breadth 89 mm, height 27 mm ; the breadth is thus 

 only .80 of the length, the height about .25. Mouth sunken 15 mm below 

 the sides of the test. Test rather evenly elevated from margin to apex, 

 perceptibly thinner posteriorly. Orally the test is flat near the margins but 

 soon begins to slope to the mouth. Petaloid area about 70 mm long by 60 

 mm wide. Tuberculation of test quite close and fine with 200 or more 

 tubercles to the square centimeter and 25 or so miliary tubercles to the 

 square millimeter ; the tuberculation is slightly more sparse orally than on 



« f/o«<7a/uj= elongated in reference to the form of the test. 



