OPHIURANS OF THE PHILIPPINE AND ADJACENT WATERS. 327 



Philippines; E. A. Mearns. 



Two specimens (Cat. No. 41325, U.S.N.M.). 



Philippines; J. B. Steere. 



One specimen (Cat. No. 40947, U.S.N.M.). 



Notes. — Several authors have given detailed descriptions of O. 

 scolopendrina or have published notes on the variations which it 

 shows; I shall refer especially to Loriol's memoirs ('93, p. 23, and 

 '93a, p. 407). The variations have to do especially with the form 

 and number of the arm spines, the shape of the upper arm plates 

 and of the mouth shields, and the number of the tentacle scales. 

 I have given (pi. 74) a few photographs of individuals in which 

 these variations are very marked. The two photographs (figs. 1 

 and 6) represent the dorsal surface of specimens in which the 

 upper arm plates show rather different outlines; in that shown in 

 figure 1, which was collected by the Albatross, these plates are not 

 very broad in relation to their length, and their angles are very 

 rounded; while in the other, which is from Mauritius, these plates 

 are very broad and short with sharp lateral angles; in the latter 

 the spines show a medium development, while in the first the dorsal 

 spine is remarkably thickened, recalling in that respect the com- 

 mon form in 0. erinaceus. In these two specimens the ventral sur- 

 face of the disk is more or less covered with granules. 



Figures 3 and 4 represent an individual from the Philippines, 

 not collected by the Albatross, which was sent to me with another, 

 also dried, both bearing the number 47,782. These two specimens 

 are unfortunately in rather bad condition, but I have been able 

 nevertheless to secure satisfactory photographs of them. The upper 

 arm plates are seen to be much broadened, somewhat irregular and 

 unequal in form, with the lateral angles sharp; the dorsal spine 

 shows average development ; the general coloration is brownish, and 

 the spines are ringed with white. The ventral surface of these two 

 specimens is especially interesting because of the variations in the 

 number of the tentacle scales. Most commonly the tentacle scale is 

 single; this single scale may appear even on the second seg- 

 ment of one of the arms, and it remains single on almost all the 

 following segments, save for a few exceptions. The other arms fre- 

 quently bear a single scale, sometimes and most commonly, two on 

 the earlier segments ; but beyond the disk the scale is usually single, 

 and this character is maintained throughout the whole length of the 

 arms; however, occasionally and abruptly, sometimes very far from 

 the base of the arms, the scale is doubled. 



A similar disposition is found in another individual from Batavia. 

 which is in my own collection and of which I give a photograph in 

 figure 5. There is, as a rule, only a single tentacle scale beyond 



