L860) SPOLIA ZEYLANICA. 
antennal scale does not reach the extremity of the peduncle, but is 
longer than the antennular peduncle. The rostrum does not reach 
to the extremity of the first antennular article. 
The dimensions of the body are as follows :— 
a = 18°25 mm. | be — Gr 0 ama é (= "24-0 amr 
bi —.3?6imm: b= 94-0 mm: el 10" 5 mms 
Pai 15 18 AE, 6§ = 4°8 mm. e?= 10:0 mm: 
Dr Imm, (© OS 8b 4am: | 
The large claw has been described and figured by Coutieére. 
The second pereiopod has the following proportions :— 
¢ = 7920; 1089 Cian LTE Qe ate VAS) c° = 2145; 858 
m = 8151; 1056 Coy oobraceo p = 3465; 1023 
c! = 3960; 858 Cc. — ws 20 rasee d = 1848; 429 
The third pereiopod has the propodite provided with seven or 
eight pairs of spines arranged more or less irregularly on the anterior 
side. The dactylos is a strong slightly curved hook. The following 
-are the proportions of the parts :— 
t1— 297031815 cy =) 6006; 1419 d = 2475; 495 
m = 8580; 2442 p = 6105; 1320 | 
The above dimensions are taken from a typical form of this species. * 
The rostrum varies in length. In one specimen it passes well 
beyond the first antennular article, and in another it is as long as that 
article. Normally the rostrum is only about two-thirds as long as 
the first article. 
General Distribution.—Pacific ; Maldives, Ceylon. 
EXPLANATION OF THE PLATES. 
PLATE V. 
Fig. 1.—Synalpheus biunguiculatus, var. exilipes. 
Fig. 2.—Alpheus ventrosus. 2a, frontal region of carapace, with 
antenne and antennules x 8; 2b, second pereiopod x 9; 2c, third 
pereiopod x 9; 2d, dactylopodite of third pereiopod x 21. 
PLatEe VI. 
Fig. 3.—Alpheus frontalis. 3a, frontal region of the carapace, the 
antennules, and antenne x 6; 3b, second pereiopod x 8; 3c, third 
pereiopod x 8. 
Fig. 4.—Alpheus rapax. 4a, second pereiopod x 8; 4b, third 
pereiopod x 8. 
PuatEe VII. 
Fig. 5.—Alpheus audouini. 5a, frontal region of carapace, the 
antennules, and antenne x 9; 5b, second pereiopod xX 10; 5c, third 
pereiopod x 10. 
Fig. 6.—Alpheus strenuus. 6a, second pereiopod x 4; 6b, third 
pereiopod x 4, 
