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PROCEEDINGS OF THE NATIONAL MUSEUM 



VOL. 81 



An uncinate with one end thickened, 12^ in breadth, the other 

 sharply pointed and with a wholly echinated surface, is frequently 

 present in the dermal membrane. It measures 200/a to SlO^u, long and 

 Q/x broad at the center. 



A monact measuring 300/i, in length and 25/a in breadth at the 

 center, with conical ends, occurs infrequently in the parenclaj'^ma. 

 This spicule somewhat resembles the microuncinate described by 

 Ijima in Japanese specimens, though it has much larger dimensions 

 in length and breadth; but it seems to me to show in shape and 

 constitution some similarity to the microuncinate. 



Table 4. — Measurements of 13 specimens of Sericoloplius reflexus 



1 Two other fragments not measured. 



Genus SEMPERELLA J. E. Gray, 1868 



SEMPERELLA SCHULZEI Semper 



Semperella schulzei Semper, Verb, pliys. med. Ges. Wiirzburg, vol. 1, p. 272, 

 1868.— Marsh Ai,L, Zeit. Wiss. Zool., vol. 25, suppl., p. 212, pi. 12, fig. E, 

 16, 17, 1875. — Marshall and Meyer, Mitth. Zool. Mus. Dresden, vol. 2, 

 p. 276, pis. 14, 15, figs. 18, 19, 1877.— F. E. Schulze, Abli. kiju. preuss. 

 Akad. Wiss. Berlin, 1886, p. 67; Rep. Voy. Challenger, vol. 21, p. 261, 

 pis. 51, 52, 1887. — Blackburn, Trans. Manchester Micr. Soc, 1896, pp. 57-61, 

 pi. 1. 



I have examined eight specimens of this species (Table 5). The 

 three complete and the two fragmental specimens exhibit nearly the 

 same outer configuration, but specimen H shows a somewhat different 

 outer appearance and mode of spiculation. 



