112 CRETACEOUS GASTROPODA 
no reason that jurassic forms, like Fusus Pietti, Heb. and Desl. (Bull. Soc. Linné. 
Norm. 1860, V, p. 172, Pl. VIII, Fig. 6), could not belong to the ruszyz, although 
it is certainly necessary to examine the specimens strictly and compare with the 
top whorls of the Azza, which occur with them. 
Of cretaceous species about one hundred are known, possibly a few more; they 
range from the lower Neocomien into the uppermost beds of the chalk. Many of 
them are true Fusus, others belong only to the sub-family rusm# and partly 
to that of the rvzevrrv», but for the larger number of species we are still in great 
want of well preserved specimens, and, until these have been procured, many 
doubtful points cannot be settled. Most of the cretaceous species, which were 
known up to 1864, are catalogued by Pictet in his Materiaux p. 1. Paléontologie 
Suisse, 8me. ser., p. 642, although of many of them (as I shall more particularly 
notice hereafter) we know in reality nothing more than the mere name. . 
a. Sub-family—FULGURIN 2. 
(CASSIDULIDZ, Gray, Guide, 1857, p. 10.) 
We propose this name for the sub-family, simply because it is the least 
liable to be mistaken with any of those previously adopted. Three genera can be 
distinguished in this group, Melongena, Shum. 1817 (Cassidulus of Adams and 
Gray, the name not being traceable with certainty) ; Hulgur, Montf. 1810 (Busycon of 
Adams and Chenu, a name which is equally not traceable), and Hemifusus, Swains. 
(Cochlidium, Gray). H. & A. Adams consider Iyristica, Swains. and Volema, Bolt., 
(or Pugilina, Shum.) as sub-genera of Melongena: I believe they are not even that, as 
they seem to refer chiefly to young shells of Welongena and Fulgur. The similarity 
is in fact very remarkable, which young specimens of Melongena exhibit as com- 
pared with Fulgur and Hemifusus, and the question as to the limit of these latter 
appears to be far from settled. The species are chiefly known from single shells, 
and although the animals of several of them have been observed, only few of the 
shells have been noticed in different stages of growth, which seems to be very im- 
portant, for they show remarkable alterations in the form in different stages of age. 
Adams and Chenu distribute the forms into the ruszv# and Fascrozarrp» and 
it is due to Dr. Gray to state, that he drew attention to some peculiarities as to the 
shell and the animals of those species, which ought to form this separate group. 
The head is much elongated and the tentacles very short with much thickened © 
basis, and the eyes on bulgings on the upper external sides. 
The operculum is ovate with apical nucleus, but it is not yet known in 
Hemifusus. 
The shell is remarkable for the great size of the last volution, which is ventricose, 
enveloping the greater part of the previous whorls, and when produced into a longer 
canal, asin Fulgur and Hemifusus, it is slightly notched at the end; when less 
produced, as in Melongena, it is deeply notched. The spire is comparatively short, 
