EEPOET ON THE GASTEEOPODA. 151 



Suture a slightly impressed line in the obtuse angle at the junction of the whorls. 

 Mouth oval, with a blunt angle above and another below, where it is produced into the 

 long, flexuous, and almost closed canal. Outer lip very equally arched ; it rises on the 

 body ; its edge contracts, and is cut up into a series of blunt-tipped saw-teeth, the deep 

 and narrow cuts between which run back into the front furrows of the spines ; the basal 

 one of these saw-teeth is large, flat, and very prominent. Inner lip spreads thinly and 

 widely but indefinitely on the body above ; on the base it separates from the body as a 

 thin, prominent, patulous lamina, curving round to the right lower down, leaving behind 

 it a deep chink, which continues as a furrow down the snout, where the labial lamina is 

 bent abruptly over, so as to cover and almost close the canal. H. 3"1 in (to point of spines 

 beyond apex 3 - 6). B. 0'93 (to tips of spines 2 - 2). Penultimate whorl, height 0"25. 

 Mouth, height 265 (excluding canal 072), breadth 0"5. 



This singularly beautiful species resembles most of all Murex aduncospinosus, Beck, in which, 

 however, the direction of the spines is different, standing out much more from the axis ; the 

 texture and ornamentation of the shell are quite different, the earlier whorls not being ornamented 

 with a double row of hollow squamous spines as here ; the spire is in that much higher, the whorls 

 less angulated, and the apex is a minute perfect cone of 3^- whorls. In Murex temispina, Lam., 

 the earlier regular whorls have somewhat similar, hollow, squamous spines ; but there is only one 

 row of these, and the apex is quite different. Murex tribulus, Linn., though at first sight very unlike, 

 has some very strong points of resemblance : it is a bigger, coarser shell, with shorter, fewer, and 

 more massive spines ; but the direction of all these agrees pretty closely with those in the Chal- 

 lenger specimen ; its spiral threads are enormous compared with those of the other, and are rudely 

 tubercled ; yet in neither species are there any longitudinal ribs ; though the snout is very short and 

 thick compared with that of Murex acantJwstephes, obliquely scored in connection with the spines 

 where the other is smooth and much more bent at the point, yet the bend has very much the same 

 character. In Murex trihuhis the whorls are constricted below, which makes the suture dissimilar, 

 yet the general form of the spire is not unlike. In regard to the apex I am unable to speak with 

 certainty. A specimen of Murex tribulus, which Professor v. Martens most obligingly sent me for 

 examination from the Berlin Museum, turned out to have suffered from the effects of cleaning almost 

 as much as those in the British Museum ; so far, however, as the apex was recognisable, it seemed 

 to have fewer whorls, and to be somewhat more conical but more amorphous, and the first regular 

 whorls seem to have only one row of squamous tubercles, as in Murex temispina, Lam. 



Murex cabritii, Bernhardi, as compared to the Challenger species, is a much shorter, stouter 

 form, with shorter, stronger spines, and with three rows of ribs between the spinous varices. 



7. Murex (Tribulus) aeanthodes, 1 Watson (PI. X. fig. 1). 



Murex (Tribulus) aeanthodes, "Watson, Prelim. Eeport, pt. 15, Journ. Linn. Soc. Lond., vol. xvi. 



p. 599. 



uxuvduiri;, prickly. 



