Report on the zoological collections made in the Indo-Pacific Ocean ...

CEITSTACEA. 303beyond the distal extremity of the terminal segment. " Colour (inspirit) yellowish white. The length of Dr. Coj^pinger's largest specimenis little over 8| lines (18 millim.) ; but the largest examplein the British-Museum collection is of much greater size, measuringnot less than 1 inch 2| lines (31 millim.).Two specimens were dredged in the Arafura Sea, 32-36 fms.(No. 160).There are in the British-Museum collection several specimenscollected in Torres Straits (J. B. Jukes). AU of these appear to beof the male sex. The terminal segment (only) is slightly pubescentabove.The mandible closely resembles that of C. lurtlpes as figui'cd byMilne-Edwards*, in its truncated and strongly dentated apex, sensorialappendage, and triarticulate palpus ; the maxillipede is alsoformed on a precisely similar type to that of C. hirtijjes.The form of the interantennal plate, which somewhat resemblesthat of certain -^ga' (e.g. JEga siJom/iopJiila), and of the lateral prolongationsof the second to fourth segments of the postabdomen atonce distinguish this species from Cirolana hirtipes, M.-Edw., andC. rossii, Miers, and from Cirolana (Eurydice) swainsonii, Leach, aMediterranean and West-African form, to which C. schiodtei is verynearly allied, ^ga novizealandia;, Dana, and Cirolana latistylisand orientaUs, all of them forms somewhat insufficiently described,appear to be distinguished by the much more rounded and lesstriangulate terminal segment, &c. C. arabica, Kossmann, to judgefrom his figuresf, is distinguished by the form of the rostrum,terminal segment, and interantennal plate both from this and thefollowing species.5. Cirolana tenuistylis. (Plate XXXIII. fig. B.)As this species in many particulars nearly resembles the foregoing,it may sufiice here to point out its chief distinctive characters. Theinterantennal process is narrow-linear, as in C. rossii or C. hirtipes,but the eyes are subquadrate or somewhat rounded, with very largeocelli, and each occupy less than one fourth of the total length of thefront and lateral margins of the head, which has a more prominentmedian frontal process. The antennules have the first two joints ofthe peduncle more dilated, the second very short, the third robust,but less dilated than the preceding ; the last two joints of the peduncleof the antennae are shorter than in C. scMbdtei. The third andfourth joints of the ambulatory legs are considerably dilated andmargined with stiff setse. The inner ramus of the uropoda is muchnarrower than in C. schiodtei, with the sides parallel to near theextremity, which is subacute. The length of the largest specimenis about 7 lines (15 millim.).A single specimen, I think a male, is in the collection from Prince* Atlas in Eegne Animal de Cuvicr, Crust, pi. Ixvii. fig. 8.t Zool. Ergebu. Reis. roth. Mecr. ii. p. 114, pi. viii. figs. 7, 11 (1880).