NO. 3 deichmann: holothurioidea ; part i, dendrochirota 149 



mary scales. External side of scales with pearllilce projections, rare or 

 totally lacking in j^oung individuals which may have a few loose grains. 

 Sole distinct with 1-2 marginal rows of feet. Spicules in sole slightly con- 

 cave 4-holed buttons (0.12 mm.) with relatively small holes and a 

 varying number of knobs on the surface, sometimes the knobs are united 

 by crossbars. Feet with end plate and perforated plates (0.18 mm.). 

 Tentacles with broad perforated plates. 



Type. — Hamburg. 



Type locality. — Patagonian Bank, Lat. 46° S. 



Distribution. — The type locality and various localities in the Strait 

 of Magellan. 



Specimens examined. — Various individuals from Albatross Station 

 2777, and 2 received from the Museum in Buenos Aires. 



Remarks. — The species is mentioned because it resembles Psolidium 

 ekmani. It was not secured by the Allan Hancock Expeditions and it 

 seems not likely that it will be found in the Panamic region. 



3. Psolus diomedeae Ludwig 

 Plate 11, Figs. 9-10 



Psolus diomedeae Ludwig, 1894, p. 136, pi. 14, figures 1-3. — Fisher, 

 1907, p. 717 (passim). 



Diagnosis. — Small form (sole less than 2 cm.) with enormous oral 

 and anal valves; radial teeth present inside to the valves. Dorsal scales 

 few and large, 2-3 between oral and anal valves; scales covered by few 

 but large grains; sole with marginal feet. Spicules in sole strongly 

 knobbed plates with 4 central holes and smaller marginal ones. (Feet and 

 tentacles not examined.) 



Ty/.^.— U.S.N.M. 



Type locality. — Off Cocos Island, Costa Rica. 



Distribution. — From Gulf of California to Ecuador including Gala- 

 pagos. 



Depth. — From 7-80 fms. 



Specimens examined. — The type in Washington and the following 

 specimens from the Velero stations : 

 143-34. Wenman Island, Galapagos, 100-150 fms., Januaiy 11, 1934, 



1 specimen. 

 213-34. La Plata Island, Ecuador, 7-10 fms., February 10, 1934. 38 

 specimens. 



