148 THE VOYAGE OF H.M.S. CHALLENGER. 



Habitat. — Andaman Islands and Bed Sea (British Museum). 



After much hesitation, I am convinced that Murex nigrospinosus of Reeve is a good species, and 

 it is the more necessary to say so in the face of the hopeless confusion threatened by revolutionary 

 processes in reference to this and many other species. That many species are badly denned is 

 certain, and the abolition of these on evidence of identity really adduced is a true service ; but to 

 slump species on superficial resemblances, merely because their distinctive features are not easily 

 recognised, however striking when once known, is only to return to chaos. Mr Tryon can hardly 

 have had before him correctly defined and well-preserved specimens of this species and of Murex 

 tribulus, Linne, when he asserts (Manual of Conchology, loc. cit.), that Reeve's species is merely a 

 colour-variety of that of Linne. The real difficulty in distinguishing them lies in the rarity of 

 specimens in which the characteristic features have been spared by the dealers. The fine specimens 

 of Murex tribulus, Linne, in the British Museum are thus grievously injured. The opportunity of 

 examining a specimen somewhat better preserved I owe to the kindness of Professor v. Martens, 

 who sent it me from the Berlin Museum. The precise form of the apex I cannot determine, so 

 severely has it been cleaned, but it is evidently larger than that of Murex nigrospinosus, with a broader 

 base ; the succeeding whorls of the spire (of which there are two without varices) are larger, more 

 scalar, of more rapid increase, and have each nine comparatively large, distant, tubercled, squamous 

 ribs, scored by two strongish spiral threads. In Murex nigrospinosus the apex is a little rounded 

 knob, consisting of barely two rounded polished whorls, of which the tip is smooth, and the second, 

 which is scarcely larger than the first, has a sharp spiral thread encircling its base ; they are 

 separated by a well-impressed suture. These are succeeded by about 2^ unvarixed, high, rounded 

 whorls of slow increase, each crossed by 13 small rounded ribs and scored by 4 fine spiral threads. 

 There are many other obvious differences, such as the greater height of the spire with fewer whorls 

 in Murex tribulus, Linne, diversity of sculjjture, peculiarity of arrangement and greater shortness 

 of spines ; but these are recognisable in any ordinarily well-preserved specimens. 



4. Murex (Tribulus) tenuispina, Lam. 



Chemnitz, Conch Cab., vol. xi. p. 103, pi. clxxxix. fig. 1821, pi. cxc. fig. 1822. 

 Murex tenuispina, Lamarck, Anim. s. vert, vol. vii. p. 158, and (ed. Desh.) vol. ix. p. 566, sp. 4. 

 ,, ,, Deshayes, Encycl. method., vers. vol. iii. p. 896, No. 4. 



„ ,, Kiener, Iconographie, p. 5, sp. 2, pi. vi. fig. 1, pi. vii. fig. 1. 



„ „ Quoy and Gaimard, "Astrolabe" (Zool.), vol. iiL p. 528, pi. xxxvi. figs. 3, 4. 



,, ,, Sowerby, Conch. Illust., No. 1. 



„ tenuispinosus, Sowerby, Gen. Eect. and Foss. Shells, vol. ii. pi. ccxxv. fig. 2. 

 ,, tenuispina, Reeve, Conch. Icon., vol. iii. pi. xxi. fig. 85. 



„ „ Eoister, Conch. Cab. (ed. Kiister), p. 27, pi. xi. fig. 3, pi. xx. fig. 3. 



„ (Tribulus) tenuispina, Kobelt, Jahrb. d. deutsch. malak. Gesellsch., 1877, vol. iv. p. 145, sp. 3. 

 „ tenuispina, Brazier, " Chevert " Exped. Shells, Proc. Linn. Soc. New South Wales, vol. i. 



p. 169. 

 „ „ Sowerby, Thes. Conch., pts. 33, 34, p. 2, sp. 1, pi. ccclxxx. (i. Gen.) fig. 7. 



„ (Tribulus) tenuispina, Tryon, Manual, vol. ii. p. 78, pi. x. fig. 113. 

 „ „ „ E. A. Smith, "Alert," Indo-Pacific Collections, Moll., p. 42, No. 11. 



Station 203. October 31, 1874. Lat. 11° 6' N., long. 123° 9' E. Philippines. 20 

 fathoms. Mud. 



