190 
Pectuncuuus sericatus. Pect. testd orbiculari, Pectiniformi, de- 
pressiusculd, albidd, rosaceo-fusco sparsim tinctd et maculata, 
epidermide sericé crassd indutd ; radiatim sulcatd, sulcis subdi- 
stantibus ; intus albd. 
Conch. Icon., Pectunculus, pl. 9. f. 49. 
Hab. Island of Tortola, West Indies. 
This exceedingly delicate shell is remarkable for its glossy silken 
epidermis; the hinge-shelf in the interior of each valve is nearly as 
broad and solid as that of the Pectunculus strigilatus, and the teeth 
are as closely set; the shell altogether exhibits many characters in 
common with that species, but no indication of the peculiar manner 
in which it is attenuated towards the umbones. 
This is the only specimen I have seen at present. 
Precruncutus tivipus. Pect. testd orbiculari, tumidd, inequilate- 
rali, antice angulatd ; longitudinaliter radiatd, radiis latis, eleva- 
tiusculis, subtilissime striatis, rubido-fuscis, marginem versus livido- 
cesiis, epidermide pilosd plus minusve indutis; radiis anticis 
creberrimis ; umbonibus recte incurvis, maculis albidis perpaucis 
circumsparsis ; intus albd, medio purpureo-nigricante tinctd et 
maculata. 
Conch, Icon., Pectunculus, pl. 9. f. 51. 
Hab. Red Sea. 
The general outline of this fine species is exactly the same as 
that of a worn discoloured shell figured in Chenu’s ‘ Recueil de 
Coquilles’ in illustration of the Pectunculus undulatus of Lamarck, a 
species which I cannot identify ; its detail of character is however 
quite at variance with the description. ‘‘ The longitudinal grooves 
of the P. undulatus,’ says Lamarck, ‘‘ are very apparent,” whilst this 
shell, which is in the finest possible condition, cannot be said to be 
grooved at all, the elevated rays are so superficial. ‘There is also 
no indication of any waved spots on the body of the shell, nor of any 
streaks on either side of the ligamentary area ; the rays are moreover 
characterizedgby a particular style of grey livid painting, which is 
unquestionably of great specific importance. 
Precruncutus Dezssertit. ect. testd orbiculari, tumidiusculd, 
subsolidd, inequilaterali, altitudine longitudinem equante ; radiatim 
sulcatd, sulcis numerosis, profundis, subtilissime striatis, liris in- 
termediis sublilissime granuloso-corrugatis, longitudinaliter in- 
cisis ; albd, fasciis pluribus aurantio-brunneis transversim undatd, 
intervallis fusco lineato-punctatis ; intus albd, antice rubido-purpu- 
reo tinctd. 
Conch. Icon., Pectunculus, pl. 9. f. 52. 
Hab. ? 
I have named this beautiful shell, at the desire of Mr. Cuming, 
after the very highly-respected individual to whom he is indebted 
for it; though it is not without feeling some degree of compunction 
that the peculiarities above noted may be merely certain modified 
conditions of the Pectunculus assimilis. It is true that the shell is 
rounder and more swollen, and consequently without that angular 
