Parxer.—On the Structure of the Head in Palinurus. 807 
I am greatly indebted to Mr. T. F. Cheeseman, F.L. S., of the Auckland 
Museum, for procuring me a spirit specimen of Palinurus vulgaris, and to 
Mr. W. A. Haswell, M.A., and Mr. T. W. Kirk, M.A., for much needed 
information respecting species of Palinurus in the Sydney and Wellington 
Museums of which I was unable to obtain either specimens or accurate 
descriptions. 
I shall be very grateful to anyone who will furnish me with descriptions 
of the head in Palinurus longimanus, M.-E., P. frontalis, M. -E., Palinurellus, 
Boas, and Palinustus, Alph. M.-E., or, still better, who will procure me speci- 
mens of these forms. 
EXPLANATION OF PLATE XXV. 
Reference Letters, 
ant. 1, antennule. 
ant. 1’, articular cavity for antennule. 
ant. 2, antenna. 
ant. 2, articular cavity for antenna. 
ant. st., antennulary sternum. 
bc., basicerite. 
cl. pr., clasping processes. 
e., eye-st 
e.cx.pl., ili coxal plates. 
lates 
fl., flap of movable part d stridulating organ, 
g., groove on lateral surface of antennulary sternum, for tubercle (t. j 
h., dorso-internal hinge of antenna. 
i. cx, pl., internal coxal a 
oph., ophthalmic segmen 
p., ridged pad of soit 2d of stridulating organ. 
p. ez. pl., posterior coxal plates. 
pre. pr., procephalic processes. 
r., ridge on antennulary sternum 
s., smooth surface on antennal sternum forming fixed part of stridulating organ. 
s. or. sp., supra-orbital sp: 
t., guiding tubercle of ola portion of stridulating organ. 
N.B.—All the figures are diagrammatic, unessential details (spines, tubercles, ete.) 
being omitted 
- Fig. 1, Longitudinal vertical section of the head of Palinurus edwardsit. 
| Palinu 
” ” ” ” 
3. 
4. dpi: part of rosi of Palinurus avarii seen from above. 
5. di i Palinurus vulgaris. js 
6. . Palinurus interruptus 
7. oli ea of Palinurus vulgaris, Es the loft side. 
8. Proximal end of antenna of Palinurus vulgaris, from the inner side, 
A II 
