the Lingual Dentition in the Gasteropoda. 243 
Bullia and Phos are, in all probability, also members of this 
family ; but only those genera or, more critically, those species 
have been introduced whose Buccznotd character has been de- 
termined by their lingual dentition, either actually figured or 
satisfactorily described. The list already includes some of the 
principal genera, and will, no doubt, be soon very considerably 
augmented when the information and research of other natu- 
ralists is brought to bear upon it in the manner above indi- 
cated, 
MURICID&. 
Lingual dentition triserial, the distinctive feature of which is 
having strongly curved sémple acuminate teeth in the pleure ; 
and the origins of the central teeth are usually in bold relief 
upon the basal plates. 
Systematic Name. References and Remarks. 
Murex tenuispina...... Personal observation, preps. and drawings. 
trunculus ......+. Figured by Hogg, op. cit. pl. 10. fig. 35. 
ran@aris’ 36... 05. « Mr. Barron’s preparations. 
ermaceus .. 6. fs. Forbes & Hanley, pl. TT. fig. le. 
Purpura lapillus ...... Mr. Barron’s preparations ; descrip.Gray, p. 20. 
Blainvilli 25...5% Mr. Barron’s preparations. 
hemastoma...... Figured by Hogg, pl. 10. fig. 36. 
Topas Francolina ...... Mr. Barron’s preparations. 
Trophon bamfium...... F. & H. pl. SS. fig. 3b. 
magellanicus ....| Mr, Barron’s preparations. 
clathratus........| F. & H., description of axile tooth. 
Monocerosimbricatum. .| Figured by Troschel. 
brevidentatum....| Mr. Barron’s preparations. 
Vitularia fiscellum ....} Description, Gay. p. 19. 
aBAHA rere e es ss Characters of genus, Gray, p. 19. 
Muricidea (Sw.) ...... Personal observation in the South Seas. 
Fusus or Colus probosci-| I have found the dentition of this species to 
dalis be as follows :—Axile plates broad, with a 
large central tooth, and a smaller one on 
either side of it. Pleural teeth simple, 
uncinate. 
Hemifusus 07 Cochlidium} Dr. Gray’s description, p. 11 (“ Teeth central, 
tuba 5-toothed, lateral, hooked, versatile”) may 
be contrasted with the above. 
The present state of the two families to which I have con- 
fined my attention in this paper shows the utter impossibility 
of classifying the Gasteropoda by the purely conchological 
method of comparing shell with shell, mdependently of the 
light which we now know may be derived from the dental 
characters. On applying to the systems of Gray, Woodward, 
and Adams the plummet of the foregoing lists, it will be 
found that, though they differ considerably ¢nter se, they all 
