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Show 992 DR. G. HERBERT FOWLER ON THE [Dec. 15, the methods employed and the general questions of distribution will be left to the last paper. SAGITTA WHARTONI, sp. n.1 (Plate L. figs. 1-3.) In external form this species resembles most nearly S. lyra (Krohn), and differs from all other species yet described in the approximation, almost fusion, of the paired lateral fins. From Krohn's species, however, it is easily distinguished by the absence of a constriction between body and trunk and by the numbers of the teeth and cirrhi. The head is large, 3-4 m m . wide and 2 m m . long in a specimen 45 m m . long. It bears on each side 8-10 stout cirrhi (Greifbaken), which are strongly curved, and of which tbe middle three are the longest. The accessory teeth (Nebenkiefer) are arranged in two series, of which the more dorsal are 3-5 in number and are short and stout; the more ventral are 5-7 in number and are slighter and longer. The neck is somewhat thinner than the body. The body tapers without constriction to the tail; the latter (post-septal region) is less than one-fourth of the total length. The lateral fins are set rather far back, the anterior being much longer and narrower than the posterior. The longest specimen measured 45 m m . The following dimensions are taken from well-preserved straight specimens, of which A was apparently uncontracted, B contracted considerably antero-posteriorly:- A* T3. Total length 30 mm. 38 mm. Head, „ 1 2 Body, „ 23 26 Tail, I, 6 10 Neck, width 1*5 3 Body, width at widest .... 2 4 Anterior fin, length 20 18 ,, width 3 6 Posterior fin, length 10 7 „ width 4 9 Tail-fin, width 3 6 It is curious that this species should not have been taken by the Plankton Expedition, which records 2 S. blpunctata from the north of Scotland. From this it is distinguished readily by the approximation (continuity) of the lateral fins. From S. hexaptera it is further distinguished by the size of the head, by the slightly more backward position of the posterior lateral fin, by the possession of more numerous cirrhi, and by the absence of the five-rayed star on the accessory teeth (cf. Strodtmann, loc. cit.). 1 In ltvoi 2io ic.Se taB rnahoinocddn tr omeiuas.ren apnorp,fc. "h A.3Sd 3ym3si-tr3ea7ml6a ,tW iphkla. rd xetvroi niC.,h aRe.tNo.g,n tahteh eHny,d"r oAgrrcahp,h feiirr, Naa tsutregaedsyc bf.ir cihentde , |