20 Af Wollebæk. | [No. 12 
— 
and as long as the fourth segment.” Faxon for this reason would 
inelude Sprencrz Barr's genus HHiconaxius under the older genus 
AxXiUus. 
From Miss Ratn»un's description and drawing”) it appears that 
Axis * spinulieauda RaTHB. possesses an unmistakable stylocerite 
and scaphocerite on the peduncle of the 2nd antennae: and the 
same is found to be the case in the species of the genus Calastacus 
which Faxon has originated. From RatH»un's work, to which 
reference has been made (pages 149—151), it would however ap- 
pear that this author denotes as stylocerite what Trysom and other 
authors have termed scaphocerite, and vice versa. 
In his nomenclature on page IV of the Challenger Expedition 
Report Vol. XXIV Spence Barr defines stylocerite as fellows: 
«Style or large spine on outer margin of the first joint of the first 
pair of antennae.”  Accordingly we find stylocerite mentioned in 
the introduction on page XXV in connection with the genus Peneus 
and Syciomia: and it is there stated that *the stylocerite does not 
exist in the Trichobranchiata,” to whieh, however, the genus Fico- 
naxius and Cheiroplatea are assigned. 
When notwithstanding we find Spence BaTE maintaining that 
these two genera in contradistinction to all the other Maerura do 
have a stylocerite, we must probably understand him to mean that 
they are the only two genera of the Macrura which have a stylo- 
cerite on the 2nd pair of antennae. HEven if this were the case, 
Spence Bare would not be consistent in his definition and employ- 
ment of the term stylocerite. 
It is very natural that the genus Hiconaxius, which was estab- 
lished by Spence Batz owing to the presence of stylocerite and 
seaphocerite, should be done away with when it became elear that 
these spines were not, as he imagined, peculiar to his three species 
of FHiconaxius, but were found also in previously discovered species 
of the genus Axius, from which the genus Hiconaxius is divided 
off. Nor would it be rational to set up new genera because of an 
inconsiderable difference in the length of these spines, when the 
spines themselves are generally speaking conspicuously developed. 
Nevertheless if we examine the oral parts of OC. crassipes which 
so far as we know, in the case of the 3rd maxilliped at any rate, 
1) Mary J. Ratapun: "Decapod Orustaceans of the North West Coast of 
North America.” Harriman Alaska Expd. with co-operation of Washington Academy 
of Science. New York 1904. Pages 149—150. 
225 
