458 Rev. A. E. Eaton on two Terrestrial Isopoda. 
Mr. Willemces-Suhm, who had the opportunity of examin- 
ing this animal when fresh from the sea, says, in his notes, 
that it is transparent, and that the alimentary canal, inclu- 
ding the cesophagus and stomach, was of a bright red colour, 
while the hepatic lobes were yellow. 
He also says that the dorsal spine-like teeth are arranged 
in longitudinal rows, one of which traverses the median line, 
the others run in pairs, making a series of four. The posterior 
_ margin of the carapace is also similarly armed with teeth. 
The pleon has similar spine-like teeth on each of the six 
somites, both laterally and in the median line. ‘The telson is 
also spinous, and has the terminal extremity beautifully fringed 
with hairs. 
LIII.—Note on Platyarthrus Hoffmanseggii, Brandt, and 
Helleria brevicornis, Hbner, Terrestrial Isopoda. By the 
Rey. A. E. Eaton, M.A. 
Tue frequent occurrence in stone-sheltered ants’ nests of 
Platyarthrus Hoffmanseggit has led popular authors to write 
about its habits; and-reputing it to be blind, they reckon it 
an animal which has lost, by disuse, the faculty of vision 
[compare Lubbock, ‘ Ants, Bees, and Wasps,’ ed. 2, p. 75 
(1882) ]. In most of the published descriptions it is posi- — 
tively stated to be eyeless ; and in the remainder no mention 
of eyes ismade at all. Quite recently, however, I have ascer- 
tained that it is provided with eyes in the usual situations. 
Each of them is composed of several well-formed ocelli placed 
close together in a rounded group; but they are destitute 
of pigment. It is easy to confound them with the minute 
bluntly conical asperities with which the general surface 
of the head is beset. It is as sensitive to light as other 
Oniscidee. 
In the early part of 1868 Ebner described a genus Helleria, 
allied very closely to Zy/us, Lat., founding it upon a species 
indigenous to Corsica, Elba, and Sardinia, which he named 
H. brevicornis. In 1879 Budde-Lund changed the name of the 
genus to Syspastus, doubtless because he supposed Hellerta to 
have been preoccupied in zoology. But Helleria, Norman, a 
genus of the Gammarid, dates only from December 1868 
(and therefore must be renamed); and Helleria, Czerny, a 
genus of the Aigidee, is more recent still (1870). Consequently 
Helleria, Ebner (1868), has priority, and Syspastus, Budde- 
Lund, takes rank as a synonym. Marschall misprints the 
name of the author, reading Erber for Ebner. 
Chepstow Road, Croydon, 
November 15, 1882. 
