270 
REPORT ON ZOOLOGY, MDCCCXLlt : 
PYCNOGONIDES. 
This order has received an accession of new species from H. Goodsir 
(James. Edinb. New. Philosoph. Journ. xxxii. p. 136, t. 3) : Phoxichili- 
dium globosum (with globular swollen thighs), from Orkney ; Pallene 
circularise from the Frith of Forth ; Pephredo hirsuta, from the German 
Ocean ; Nymphon Johnstonii (ibid.) ; N. pellucidum and N. minutum, 
from the Frith of Forth ; N. spinosum, locality not given. The new 
genus Pephredo, has, as characteristics : claw-shaped jaws ; three-jointed 
palpi, of the length of the short cylindrical proboscis ; six -jointed egg- 
bearing tarsi ; the first tarsal joint small ; no accessory claws ; in general, 
it resembles Phanodemus cost. (S. Archiv. 1843, 1 Bd. p. 181), but 
differs in the form of body, which is narrow and contracted like Nymphon, 
while in the former the body is orbicular ; so that the two genera cannot 
be united. Pephredo comes nearer Nymphon. 
CEUSTACEA. 
Cantor has cursorily made known the Crustacea observed at Chusan 
(Ann. Nat. Hist. ix. p. 490). These are, — Carcinus olivaceus, new 
species (greenish-olive above ; beneath white, with a single spine on the 
anterior part of the internal margin of the femur) : Sesarma tetra- 
gona, new species (above green, beneath greenish-grey ; arms and claws 
red) ; Ses. quadrata, Edw. ; Palcemon ornatus, 01. ; Squilla mantis, F. ; 
and an undefined Limulus. 
DECAPODA. 
Rathke has made a contribution to the natural history of the Decapoda, 
in the Neuest Schr. der Naturf. Gesellsch. in Danzig, 3 Bd. 4 Hft. p. 23, 
which finishes the notices, cursorily made already in vol. vi. of these 
Arch. 1 Bd. p. 241, on Astacus marinus, Pagurus hernhardus, Galathea 
rugosa, and Hyas araneus ; and, at last, after repeated investigations 
into the development of the river cray-fish, he comprehends the history 
of the metamorphosis of the Decapoda under the following general 
points of view : — 
1. Thomson’s important discovery of the metamorphosis of the Crus- 
tacea, formerly doubted by the author, is completely confirmed. — 2. Per- 
haps no Decapod comes from the egg complete in exterior form ; even 
in the river cray-fish, in which the deviation is smallest, the want of 
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