valves in young specimens (fig. 2 a) comes near to that of the same parts in D. Hoeki as 

 figured by Stebbing. It is undoubtedly the most common form of Dichelaspis occurring in the 

 Malay Archipelago; it was collected during the cruise of H.M.S. "Siboga" at about 20 different 

 stations at depths varying from g to 112 m. They seem to be most numerous at depths not 

 exceeding 55 a 60 m. and are found attached to different objects: stems and small branches 

 of horny corallines, algae etc. 



The specimens from different localities and depths show considerable variety in their 

 general outline, size, shape of the valves, hairiness, the more or less complete calcification of 

 the valves etc. : no doubt the species would present a very valuable material for the study of 

 variation of a wild animal living under different conditions. 



The following is a list of the stations where specimens of this species were collected. 



Stat. 47. April 8 — 12, 1899. Bay of Bima (north coast of Sumbawa). Depth 55 m. Numerous 



specimens attached, with Scalpellum rostral ii/n Darwin, to ditterent small stems. 

 Stat. 60. April 27 — 28, 1S99. Haingsisi, Samau Island, Timor. Depth 23 m. Numerous small 



specimens. 

 Stat. 65". May 6, 1899. Lat. 7°o S., Long. 120° 34.5 E. Depth 120 m. at least; coral bottom. 



One specimen. 

 Stat. 71. May 10 — June 7, 1899. Makassar and neighbourhood. Depth up to 32 m. 8 specimens. 

 Stat. f/. June 10, 1899. Lat. 3°27'S., Long. II7°36'E. Depth 59 m. Fine grey coral sand. 



One fairly large specimen. 

 Stat. 80. June 13, 1899. Lat. 2°25'S., Long. II7°43'E. Depth from 50 — 40 m. Bottom: fine 



coral sand. One large, three smaller specimens attached to a piece of coral. 

 Stat. 99. June 28 — 30, 1899. Lat. 6°7'.5 N., Long. 120° 26' E. Depth from 16 — 23 m. Litho- 



thamnion-bottom. 3 specimens, one attached to a small Lamellibranchiate Mollusc. 

 Stat. 125. July 18 — 19, 1899. Anchorage off Sawan, Siau Island. Depth 27 m. Bottom: stone 



and some Lithothamnion. 3 specimens, with very short peduncles and very hairy. 

 Stat. 133. July 25 — 27, 1899. Anchorage off Lirung, Salibabu Island. Depth up to 36 m. 



Bottom: mud and hard sand. 4 specimens. 

 Stat. 144. Aug. 7 — 9, 1899. Anchorage north of Salomakie (Damar) Island. Depth 45 m. 



2 specimens. 

 Stat. 164. Aug. 20, 1899. Lat. i°42'.5 S., Long. I30°47'.s E. Depth 32 m. Bottom: sand, 



small stones and shells. Numerous small and larger specimens. 

 Stat. 172. Aug. 26 — 28, 1899. Gisser; anchorage between this island and Ceram-Laut. Depth 18 m. 



Coral- and Lithothamnion-bottom. A dozen specimens with perfectly calcified valves. 

 Stat. 213. Sept. 26 — Oct. 26, 1899. Saleyer anchorage and neighbourhood. Depth up to 36 m. 



Extremely numerous specimens attached to threads of corals, to one another etc. 

 Stat. 257. Dec. 11, 1899. Kei Islands, Du-roa Strait. Depth to 52 m. Bottom: coral.' 3 specimens. 

 Stat. 258. Dec. 12 — 16, 1899. Kei Islands, Tual anchorage. Depth 22 m. Bottom: Lithotham- 

 nion, sand and coral. Several specimens, some of them very large. 

 Stat. 274. Dec. 26, 1899. Lat. 5°28'.2S., Long. I34°S3'.9E. Depth 57 m. Bottom: sand and 



shells; stones. Numerous specimens, together with small barnacles {Ba/ani/s f^pcc). 

 Stat. 282. January 15—17, 1900. Lat. 8°25'.2 S., Long. i27°i8'.4E. Depth 27— 54 m. Bottom: 



sand, coral and Lithothamnion. Numerous specimens attached to polyps etc. 

 Stat. 289. Januari, 20, 1900. Lat. 9°o'.3S., Long. 126° 24^5 E. Depth 112 m. Bottom: mud, 



sand and shells. Two specimens. 

 Stat. 315. February 17 — 18, 1900. Anchorage East of Sailus Besar, Paternoster Islands. Depth 

 up to 36 m. Bottom: mud and sand. Three specimens. 



I have pleasure in naming this beautiful and interesting species after Dr. H. F. Nierstrasz, 

 one of the Zoologists on board H. M. S. "Siboga". 



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