CRUSTACEA OF THE MERGUI ARCHIPELAGO. QS 
This most interesting species, which I dedicate to the author 
of the important Report on the carcinological Collections made 
in the Indian Ocean during the voyage of H.M.S. ‘ Alert,’ pre- 
sents a remarkable transition between the genera Coralliocaris 
(Gdipus, Dana) and Harpilius, the small curved claws of the 
legs of the last three pairs being armed with a-small accessory 
tooth on their inner (inferior) margins, quite as in the genus 
Coralliocaris. But Harpilius Miersi is also remarkable, because 
in general appearance and in many particulars it presents a 
striking resemblance to two allied species, viz. Anchistia auran- 
tiaca, Dana, from the Fiji Islands, and Harpilius inermis, Miers, 
from the Australian Seas, especially to the former. 
The body of Harpilius Miersi is somewhat compressed, espe- 
cially the postabdomen, which is curved downwards, like that 
of Harpilius inermis; the surface of the body appears smooth 
to the naked eye, but is really minutely punctate when ex- 
amined under a magnifying-glass. The anterior margin of the 
carapace is armed with a small antennal spine above the basal 
joint of the external antenne. The upper surface of the cara- 
pace is rounded. ‘The rostrum is very characteristic: it is 
strongly compressed, ensiform, longer than the eyes, and reaches 
to the middle of the penultimate joint of the internal antenne; 
in a dorsal view it appears acute at its apex, and much resembles 
that of Anchistia aurantiaca. In a lateral view it appears 
lamellate, being nearly four times as long as broad; in that 
position also the denticulation of the rostrum becomes visible 
by means of a magnifying-glass. The upper margin is almost 
entire throughout its length, except quite at the distal end 
(fig. 8), where it is armed with four small acute teeth, placed 
immediately before the acute tip; the under margin also is almost 
entire, presenting only one small tooth at the distal end, placed 
immediately below the second or third tooth of the upper margin ; 
the tooth of the under margin, however, is much smaller than 
the teeth of the upper margin, and can only be distinguished by 
means of the microscope. The terminal segment of the post- 
abdomen is rounded above, but gradually and considerably narrows 
towards its distal end, which bears some sete; its lateral margins 
are unarmed. The peduncles of the upper antenne are longer 
than the rostrum, which reaches to the middle of their penultimate 
joint, but are a little shorter than the scale of the external antenne ; 
the last two joints have almost the same length. The external 
18* 
