NO. 2 DEICHMANN : HOLOTHURIOIDEA ; PART II, ASPIDOCHIROTA 327 



Remarks: The Hancock material has demonstrated how variable 

 the color is in this species. The larger of the two specimens from San 

 Lucas is sufficiently well expanded to permit a description of the color 

 pattern. The dorsal side is light brown with darker papillae of varying 

 size and with a white area around the base ; in addition there are seven 

 dark spots in two rows on the back. Ventrally the animal is almost white 

 with dark brown appendages and a white line stretching down along the 

 midline. 



From the same locality and depth the expedition was fortunate 

 enough to secure a well expanded specimen, about 3 cm long, with very 

 interesting spicules. The inner layer of buttons appears to be totally lack- 

 ing, as is so often the case in the younger stages, but the characteristic 

 tacklike tables are present in numbers, though scaled down to the size 

 of the animals. In addition one finds numerous juvenile tables with a 

 delicate disk, complete and with slightly spinous edge, and a more per- 

 fectly developed spire than is usually found in older individuals; and 

 most important, a number of large tables with cross-shaped disk and tall 

 spire, with or without crossbars and teeth ; in a few cases a narrow band 

 extends from the edge of the arms so that a complete circle is formed 

 (synallactid-type). 



In the 5 cm specimen from Clarion Island, 32 fathoms, the buttons 

 have begun to appear and are large with few knobs. The tables are 

 usually reduced as in the adult, although a few of the primitive synal- 

 lactellid tables are still present. In the remaining specimens, which range 

 in size from 8 to 14 cm, strongly contracted, the spicules are of the 

 typical form with a preponderance in the ventrum of almost flat buttons 

 with small holes. 



The species is probably more common than the few records indicate 

 but it escapes detection due to its burrowing habits. Where the conditions 

 are suitable in shallow water, it is usually taken in large numbers, as 

 Steinbeck & Ricketts records indicate. 



That it apparently does not extend far up into the Gulf of Cali- 

 fornia may indicate that it is a comparatively recent migrant from the 

 West Pacific, if the assumption is correct that it also occurs in the Indo- 

 West Pacific, concealed under an older name. It is noteworthy that no 

 representative of the genus has been taken in the Hawaiian Islands, al- 

 though this may be because the burrowing types have not been studied 

 intensively in that region, which abounds in free-living forms. 



