160 Tranmctions. 



Toxocidaris tuberculatus Lamarck. 



Strongylocentrotus tuberculatus, Farquhar, Ramsay, &c. 



Three individuals were collected. The largest has the following dimen- 

 sions : — Diameter, 83 mm. : height, 39 mm. : spines, 45 mm. : poriferous 

 zone — above, 6 mm. ; below, 8 mm. : coronal plates, 20 mm. 



There are 10 or 11 pairs of pores in an arc; but below the ambitus, 

 where the zone widens out, the pores are pressed together into a nearly 

 horizontal line of 7 pairs in the widest, decreasing towards the peristome. 



Colour. — When alive the " colour of the spines is greenish-brown." 

 WTien dried they are dark olive-brown, greenish towards the base, with a 

 rosy tinge near the tip. The rosy tip is much more distinct in the spines 

 below the ambitus and around the peristome, perhaps because they have 

 been less bleached. They are here more distinctly green, more truly olive, 

 than above the ambitus ; those immediately round the peristome being 

 decidedly green. The test when dried is pale brown. 



ioca%.— Sunday Island (9/11/1908). Mr. Oliver writes, " This is the 

 most abundant sea-urchin on the Kermadec Islands. Occurs everywhere 

 among the rocks, from low-water mark down, in rock-pools. It was also 

 seen at Macauley Island and French Rock. Continued westerly winds 

 during the winter months shifted the sand from the low flat beach on 

 ihe north of h'unday Island towards a boulder coast, burying the rocks 

 for a considerable distance along the shore to above the level of low tide. 

 This had the effect of driving thousands of these sea-urchins inshore, where 

 a large proportion perished." 



This species has already been recorded from these islands by Farquhar 

 (1906), who received specimens from Mr. Haylock. There is a specimen 

 in the Dominion Museum said to have been collected at Wellington ; and 

 I am informed that at one time there was a specimen in the possession of 

 Mr. Suter which had been collected at Mokohinou, Auckland. 



Distribution. — -New Zealand, New South Wales, Lord Howe Island, Japan, 

 China. 



Remarks. — I have followed Hamann (in Bronn's " Thierreichs ") in 

 placing this species in the genus Toxocidaris, which Agassiz erected for 

 those species of Strongylocentrotus in which the poriferous zone assumes 

 a " petaloid " form below the ambitus. 



It appears that the colour of the spines is very variable. Agassiz (1872, 

 p. 150) says, " The colour of the spines varies from dark violet to black." 

 Ramsay (1885, p. 16) gives them as " uniform olive to olive-brown," and 

 refers for the first time to the flattening of the spines below the ambitus. 

 Agassiz and Clark (1907, p. 122) write that the Japanese specimens 

 " are all (with one exception) large and of a very deep reddish-purple 

 colour." 



As Agassiz' account of the spines of S. erythrogrammus agrees better with 

 that presented by my specimens — viz., " olive brown, tipped with violet " 

 — I hesitated as to the correctness of my identification, especially as he 

 remarks that the test of S. tuberculatus " when dry and denuded is usually 

 greenish, the lower surface whitish." He makes no reference, however, to 

 the colour of the other species ; but from the petaloid widening of the 

 poriferous zone, and the character of the spines and their proportions. I 

 believe that I am correct in placing these specimens under this species. 



