O72 
CLASS IX. 
marine creatures appears to be a mistake’. They are dull animals 
living on the beach under stones, or on marine plants. They 
undergo, according to the observations of KRroryrer, a remarkable 
metamorphosis, and have at first only two pairs of short feet, and a 
short, thick, undivided body. Afterwards a third pair of feet, still 
short, appears, and only in a succeeding state is the fourth pair added 
to them. 
That division of the body which lies in front of the first pair of 
feet and bears the eyes above, is in some more, in others less dis- 
tinctly distinguished from the first ring of the thorax. To this 
division are attached on the under surface two filiform parts, consist- 
ing of 7—11 joints, which in some species occur only in the female 
and serve for the attachment of the eggs. In some species in front of 
these are two pairs of other parts at the base of the conical sucker, 
of which the first pair, shorter and broader, mostly forms a shear- 
shaped nipper, the second is filiform, and consists of five, sometimes 
of more joints, and is commonly denoted as a feeler (palpus). It 
is worthy of remark that the first-named, the nippers or mandibule, 
occur also in the earlier imperfect state of those species which, in 
the perfect form, are not provided with them. 
The hardness of the integument of these animals renders it less 
probable that they breathe by the skin. Probably they have an 
intestinal respiration, such as occurs also in other animals. 
Compare M.T. BrurEnnicu Entomologia, Haffnie, 1764, 8vo. p. 84, with 
the explanation of fig. 4 (Pycnogonum) of Tab. ; various figures are found 
in MUELLER Zool. danica Tab. 119, in LeAcH Zoolog. Miscellany, 1. Pl. 13, 
19, SAvIGNY Mém. s. 1. Ant. 8. v. I. p. 54, Pl. v. fig. 3, GUERIN Iconogr., 
Arachn. Pl. 4, &e. 
G. Jounston Mag. of Zool. and Botany, 1. 1837; A. Parippi Neapoli- 
tanische Pycnogoniden in Ericuson’s Archiv f. Naturgesch. 1X. 1843, 
s. 175—182, Tab. 1x. figs. 1—3; H. Kroryrer Naturhist. Tidsskrift, 11. 
1840, pp. 299—306, Tab, 111. and ibid. new series, I. 1844, pp. 90—139 ; 
H. D. Goonsir On the specific and generic characters of the araneiform 
Crustacea, Ann. of nat. Hist. X1v. pp. 1—4, Pl.1; DE QuaTREFAGES Mém. 
sur Vorganisat. des Pycnogonides, Ann. des Sc. nat. 3e Série, Tom. Iv. 1845, 
Zool. pp. 69—83, Pl 1. 11; DugaRvIn in Compt. rend. 1849. T. XXIX. p. 28; 
ZENCKER in MUELLER’S Archiv f. Anat. wu. Phys. 1852, 8. 379. 
A. Mandibles and palps (first pair of maxille according to 
KROEYER) none. Accessory feet (second pair of maxilla KRroey.) 
in females alone. 
1 Fasricius considered the parasitic crustacean, named by Linnxus Oniscus Cett, 
to be a species of this genus Pycnogonum. 
