ACARINA FROM THE JUAN FERNANDEZ ISLANDS 581 
If we examine the diagnoses and drawings of these two species, QO. cr7z- 
nitus and O. longior, we find that they differ so profoundly in some essential 
respects, that it seems very doubtful whether they belong to the same sub- 
genus. In O. dongzor the pseudostigmatic organs are placed exceptionally far 
forwards, whereas in O. crinztus they are placed further backwards. In O. 
longior the anterior margin of the hysterosoma is rounded, and the posterior 
part of the propodosoma has no projections; furthermore the interlamellar hairs 
are very small and inconspicuous and inserted a little in front of the pseudo- 
stigmata, and the lamellar hairs are either absent or placed so far forwards as 
to be rostral hairs, in which latter case the rostral hairs are either placed sub- 
marginally and not seen or missing. In O. crinztus, on the other hand, the 
interlamellar hairs are long and both lamellar and rostral hairs are visible, 
placed closely together far forwards. The antero-lateral angles of the hystero- 
soma are sharp and project forwards and in the posterior part of the propodo- 
soma there are four semicircular, depressed areas surrounded by ridges. 
In 1913 BERLESE created a new subgenus Odontocepheus (p. 95) character- 
ized as follows: »Notogastro dentibus in margine antico, linee mediz longi- 
tudinali sat. adpressis duobus. Margo posticus cephalo-thoracis dentibus duo- 
bus, qui supradictos notogastrii attinguent. Cetera ut in subgen. Caradodcs. 
Typus: Zegeocranus elongatus MICH.» 
It is quite inconceivable how BERLESE came to make e/ongatus the type 
of this subgenus, because MICHAEL, who gave an excellent description of this 
species, accompainied as usually by beautiful drawings, does not mention nor 
delineate any teeth on the propodo- or hysterosoma at all! 
And in order to add to this confusion BERLESE in the same paper de- 
scribes and delineates a species Ofocepheus dameoides (p. 93, fig. 66 pl. 6) which 
has these four teeth. We can only suppose that some error has crept in 
BERLESE’s. paper and that in reality he intended to make O. damaoides the 
type of the new subgenus although by an oversight he made C. elongatus 
the type. 
The fact remains, however, that the genus includes two species which, 
according to the modern conception of generic differences amongst the Ori- 
batei, do not belong to the same genus. 
O. longior having been described first, this species must be considered 
the type of the genus Ovsocepheus, the diagnosis of which I propose to for- 
mulate as follows: »Body very elongated, three times as long as it is 
wide, pseudostigmata placed far forwards, interlamellar hairs very 
small, anterior margin of hysterosoma convex, rounded, tectopedia 
II very large, triangular in outline from dorsal view, no true lamelle. 
This leaves O. crzndtus out and as it can neither be placed in Carabodes 
sensu stricto nor in Odontocepheus a new genus must be created, which will 
“also include the new species from Juan Fernandez. As a further investigation 
of the tropical acarina-fauna will undoubtly yield many new forms more or less 
related to this genus, I think it is most appropriate to defer the establish- 
ment of a new genus until more forms have been investigated. 
Length 1370 u, width 680 », length of propodosoma 250 wu. 
Colour pale straw yellow, with darkbrown legs. 
