OCR Text |
Show 950 DR. H. J. HANSEN ON CRUSTACEANS [Dec. 1, B. On the ext. br. of,urp. the ciliated part occupies more than the half of the exterior margin. S. cornlculum, Kr., H. J. H. (S. laclnl-atus, Kr.) S. utrlnquedens, Bate. S. longlrostrls, Bate. To this group further belong the following species : S.praecollus, Bate, S. semlarmls, Bate, S. longicaudatus, Stimps., S. rentes (Stimps.), and S. (Sciacaris) telsonls, Bate. All are but larvae. GROUP II. Mxp.3 considerably or much longer than trl.3, Its 4 proximal conslderablg or (generally) very much Incrassated or partially inflated in proportion to the joints in trl.3, its two distal joints very short bristles or totally naked along the one margin, the sixth joint with a number of spines very different in length along the other margin, and a feebler armature may also be found on tbe fifth joint. A. The adult and the older larvae with two branchiae above trl3., and tbe sixth joint of mxp.3 divided into 5 subjoints. The adult with a comb of very numerous short spines along the one margin of the sixth joint and of the distal part of the fifth of mxp.3 The larvae with short eye-stalks. f *S. henseni (Ortm.). \ S. sargassl, Ortm. B. The adult aud the older larvae with one branchia and a lamella above trl3., and the sixth joint of mxp.3 divided into 4 or 6 subjoints. Tbe adult without any comb on mxp.3 Tbe larvae with moderately long or very long eye-stalks. (The edwardsll-grou]).) a. On the ext. br. of urp. the exterior margin is ciliated in the whole length or (in the larvae) at least in c. ^-1 of the length.1 *S. ediuardsl, Kr. S. oculatus, Kr. On the ext. br. of urp. the exterior margin is ciliated at most in g of the length. a. The same exterior margin is in the larvae ciliated at least in f, in the adults in more than 4- of the length. (*S. vigil ax, Stimps., H. J. H. [ S. parvidens, Bate. *S. penerinkl, Bate, H. J. H. /3. The same exterior margin is ciliated iu less than f of the length. *S. incertus, n. sp. *S. hall a, Faxon. S. armatus, Kr. 1 Here and in the following part of the tabular view I cannot include larvaj shorter than 9-10 m m . in length, as the character employed alters in the youngest slages (see later on). |