Vol. 58. |] MR. F. R. C. REED ON THE GENUS LICHAS. 81 
Section H. (Fig. 19.) 
The aberrant form O¢eratolichas gryps likewise heads an inde- 
pendent section, the characters of which 
are those of the type-species. This sec- 
Fie. 19.—Lichas gryps : Sw 4 
= ACNAS STYPSs tion also seems limited to America. 
Hall. 
Section H. 
L. (Ceratolichas) gryps, Hall. 
LI. dracon, Hall. 
| VI. Conciuston. 
In the foregoing sections of the two 
main groups all the known members of 
J the Lichadide can be naturally included. 
it is questionable to what extent 1b 
[See Zittel’s ‘Textbook of is advisable to employ subgeneric or 
Palxont.'transi.Hastman, generic names in an extended or restricted 
1900, p. 632, fig. 1315.] sense. The original conception of the 
subgenus or genus is lost by so doing, 
and its definiteness may be obscured, but the existence of newly- 
recognized transitional forms renders it difficult to draw up a 
permanent and invariable rule. The types of several different 
subgenera occasionally fall into the same section; and in such a 
case it seems desirable to apply to the section the name of the 
most typical and comprehensive form. For example, in Section A, 
Group I, Corydocephalus may be used as the title of the section. 
The sections probably may be regarded as of subgeneric rank, 
though some are not so isolated as others, and all are not of equal 
value; and only the two groups can be consideréd as generically 
separable. 
Names for the two groups seem necessary, and therefore for 
Group I the name Protolichas is proposed, and for Group II the 
name Deuterolichas. In spite of my reluctance to add to an 
already overburdened nomenclature, it does not seem possible to 
avoid giving distinctive designations to these two main divisions. 
In the case of the sections of these groups the majority 
already have names attached to them, which have been employed 
by various writers as of subgeneric value. The names Metopias, 
Arges, and Platymetopus must be, dropped because of their pre- 
occupation, and tor them may be substituted respectively Metopo- 
lichas, Gurich, Ceratarges, Giirich, and Paralichas, nom. prop. The 
two Sections C & KE of Group I may be termed respectively 
Platylichas, Gurich, and Metalichas, nom. prop., and Section D of 
Group Il Lchinolichas, Giirich, in order to complete the series 
of sectional names, which will then run as follows :—-: 
CJC. None 29. G 
