264 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



he described are not altogether due to difference of locality. Varieties 5 and 6 were 

 found associated by the Challenger in Prince of Wales Channel. Variety 7, which is 

 only variety 6 with IIIBr series, was found associated with it by the Alert both in 

 Torres Strait and in Prince of Wales Channel, and in the latter locality variety 4 was 

 obtained as well. It was therefore evident to Carpenter that the cause of these 

 remarkable variations in one and the same specific type must be attributed to some- 

 thing more than a mere change of local conditions. 



The specimen recorded by Dr. Hubert Lyman Clark from off Double Island 

 Point, Queensland, is a fine adult individual with 28 arms. There are about XXV 

 cirri, the longest with 45 segments. The color, dry, is uniformly brownish white. 



The three specimens from 10 miles southwest of Mapoon are especially fine. 

 One has 19 arms 150 mm. long, and the cirri XVI, 41-43, from 25 to 30 mm. long. 

 Another has 21 arms 150 mm. long and the cirri with 40^2 segments, 30 mm. long. 

 The third has 17 arms 130 mm. long and the cirri XXIII, 41-44, 30 mm. long In 

 these three specimens the processes on the segments of the lower pinnules are strongly 

 developed and typical. The cirri are more or less carinate dis tally. The synarthrial 

 tubercles are prominent, so that the animals are characteristically rugose. 



Of the two specimens from Port Curtis one has 14 arms 80 mm. long, and the 

 cirri XXIII, 35-40, 30 mm. long. The other has 26 arms 100 mm. long, and the 

 cirri XXIX, 35-45 (usually 40-41), 30 mm. long. The centrodorsal is 5 mm. in 

 diameter at the dorsal pole. The arm bases are exceptionally rugged with the syn- 

 arthrial tubercles large, prominent, and bluntly conical. The lower brachials are 

 very short but much swollen, with strongly projecting distal edges. The division 

 series are just in apposition laterally. The distal cirrus segments are very strongly 

 and sharply carinate, this carination standing out as a broad spine of which the 

 outer edge is almost or quite parallel with the longitudinal axes of the segments. 



The specimen from Mast Head Island is a fine example with 22 arms. 



One of the specimens from Baudin Island has the lateral processes on the seg- 

 ments of the proximal pinnules greatly exaggerated. The other is small. 



Of the specimens from Holothuria Bank six are large, very rugged, and typical 

 examples with the lateral processes on the segments of the proximal pinnules excep- 

 tionally well pronounced. These have 10, 11, 12, 13, 15, and 17 arms. One small 

 specimen has 15 arms. There are also four small 10-armed specimens. 



The specimen from the vicinity of York Sound is small. 



Dr. H. L. Clark, basing his conclusions on 50 specimens, 30 dredged at various 

 points near Broome in 9-15 meters, 18 from on or near Pearl Shoal in 9-15 meters, 

 and 2 from Norwest Islet in the Capricorns, said that the number of arms ranges 

 from 16 to 30, but the great majority of individuals with arms over 60 mm. long have 

 20 to 25. The cirri are XX-XXXII, 34-46, but small individuals often have fewer 

 segments. The largest specimens have the arms 75-90 mm. long. There is great 

 diversity in the development of the projections on the segments of the basal pinnules; 

 often they may best be designated as spines, but in other cases they must be char- 

 acterized as "wings." Light-colored individuals seem on the whole to tend toward 

 wings, while the dark-colored ones are more spinous. The correlation is, however, 

 very imperfect. 



