CHARACTERISTIC DEEP-SEA TYPES. — CRUSTACEA. 49 
pletely fill deep orbital sinuses in the front of the carapace in 
which they are imbedded. The Willemoesie have a very wide 
geographical distribution, and they are peculiarly adapted for 
burrowing in soft ooze, in which they seem to live. Some of 
the species are wonderfully transparent. They are the repre- 
Fig. 238. — Munida. +. (S. I. Smith.) 
sentatives in our seas of the fossil Eryonidz, which flourished 
in the jurassic lithographic beds of Solenhofen, in Bavaria. It 
is interesting to note that the eyes of the fossil species were 
extraordinarily developed. 
Nephropsis Agassizi (Fig. 240), the only species of Astacidea 
discovered, belongs to a genus previously known only from a 
single imperfect specimen dredged in the Bay of Bengal. The 
