88 BULLETIN 84, UNITED STATES NATIONAL MUSEUM. 



OPHIACANTHA PENTACRINUS Lutken, 



Plate 9, figs. 3-6. 

 See for bibliography: 



Ophiacantha pentacrinus LiJTKEN (69), pp. 46 and 99. 

 not Ophiacantha meridionalis LYMAN (69), p. 324. 

 not Ophiacantha pentacrinus KCEHLER (07), p. 319. 

 part? Ophiacantha pentacrinus LYMAN (78), p. 280. 

 part? Ophiacantha pentacrinus LYMAN (82), p. 199. 

 ^Ophiacantha pentacrimis VEBRILL (99a), pp. 324 and 334. 



Blake station 222. Feb. 16, 1879. Lat. 13 58' 37" N.; long. 61 04' 45" W. 

 422 fathoms; s. oz.; temp. 42.5 F. One specimen. 



Albatross station 2117. Jan. 27, 1884. Lat. 15 24' 40" N.; long. 63 31' 30"; 

 W.; 683 fathoms; yl. m. fne. s.; temp. 39.75 F. One small specimen. 



Albatross station 2664. May 4, 1886. Lat. 29 41' N.; long. 79 55' W.; 

 373 fathoms; co. s.; temp. 42.7 F. Five specimens. 



Albatross station 2667. May 5, 1886. Lat. 30 53' N.; long. 79 42' 30" W.; 

 273 fathoms; gy. s. bk. sp.; temp. 48.7 F. Two specimens. 



Albatross station 2753. Dec. 4, 1887. Lat. 13 34' N.; long. 61 03' W.; 

 281 fathoms; bk. s.; temp. 48 F. One specimen. 



Unfortunately, the specimens are not in a very good state of preservation; in 

 nearly all of them the arms are incomplete, and in the four largest ones from station 

 2664 the upper face of the disk is more or less damaged. In the latter specimens 

 the diameter reaches from 5 to 5.5 mm. ; in the others it varies between 3 and 4.5 mm. 



In my work on the Ophiurans of the Paris Museum (07, p. 319), I published, 

 concerning 0. pentacrinus, a few remarks and two drawings, one of which represents 

 the under face of the disk and the other a few stumps of the upper face, after the 

 three specimens which were gathered by the Blake and presented to the Jardin des 

 Plantes by Agassiz under the name of 0. pentacrinus. I beg to recall on the subject, 

 that Lyman, after having described under the name of 0. meridionalis an Ophia- 

 cantha found in the Caribbean Sea between 237 and 327 fathoms (69, p. 324), had 

 suggested that this species probably did not differ from 0. pentacrinus Lutken, 

 and he had definitely united it to the latter in his subsequent publications. Now, 

 I have been able to examine the very type of 0. pentacrinus described by Lutken, 

 and preserved in the Copenhagen Museum; although this specimen, which is 

 unique, is of very small size, since the diameter of the disk hardly reaches 3 mm., 

 and although its arms are broken near their bases, its characters are, nevertheless, 

 very plain. I have been most astonished to find that the three specimens of the 

 Jardin des Plantes which are called 0. pentacrinus are entirely different from it. 

 On the contrary, I have noticed that all the specimens gathered by the Albatross at 

 the three above-named stations were in perfect conformity with the type. The 

 comparison was, besides, made easier by the presence, among the above-mentioned 

 specimens of the Albatross, of two very small examples, which measure only 3 mm. 

 across the disk and which have, consequently, dimensions identical with those of 

 Ltitken's type. There can exist no doubt as to the determination of these 

 specimens. 



