282 Mr. H. H. Slater on a new Genus of Pycnogon 
peculiarity, as far as I know, hitherto unknown amongst 
Pycnogons. 
The first segment is produced into a sort of long neck, upon 
which the three pairs of appendages and the oculiferous 
tubercle are placed. 
The appendages of the first pair (maxillipeds) arise from 
the end of the u neck,” close to the base of the rostrum ; they 
are short (T45 millim.); and their terminal joint is a roundish 
knob, as in the genus Achelia. 
Those of the second pair (palpi to the first) are long and 
slender, 9-jointed, and nearly Gmillims. in length ; they arise 
from two tubercles at opposite sides of the u neck,” and near 
its distal end ; their third and fifth joints are much the longest, 
the first, second, and sixth much the shortest, the fourth and 
three terminal joints being nearly equal, and each about half 
the length of the third; the last three joints have a fringe of 
stiff hairs on their outer side : these hairs are curious as being 
of two thicknesses, the terminal third of each hair being only 
about half as thick as the basal part; there are also on the 
fifth joint a few long bristles which are similarly formed. I 
have not noticed any thing of the kind in any other genus. 
The ovigerous legs are 10-jointed, slender, and about the 
same length as the palpi; they arise near the bottom of the 
11 neck the four joints preceding the terminal claw have a 
fringe of beautifully denticulated spines ; these, with the 
bristles just mentioned of the palpi, are the only hairs or spines 
on the animal. 
The abdomen is of moderate length and clavate, its least 
diameter being at its middle. 
Colour in spirit is pale straw. 
The one specimen, from which I have taken my description, 
was dr-edged by Capt. St. John off Cape Sima, Japan ; depth 
not mentioned; bottom, sand and broken shells; date 1873. 
Presented to the British Museum by J. Gwyn Jeffreys, Esq., 
and numbered in the Catalogue 73. 28. 
Measurements. 
millim. 
Rostrum (including constricted portion) to where it 
joins the “neck”. 3-5 
Quasi-neck, to insertion of first pair of legs. 3-5 
Abdomen, length of.,. 1*35 
Total length... 11 
Breadth of body at second pair of legs. 3 
Length of leg of second pair . 16 
Total breadth (16 + 16+3). 3o 
This genus comes pretty near to Zetes as figured by Kroyer 
( loc . cit.) ; but if Zetes is there correctly represented, there are 
