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Part III. — Sixteenth Annual Report 



be doubt as to the correct identification of female specimens of this species, 

 there need be none as regards male specimens, the strongly-marked 

 character of the first pair of coxal plates in the male being quite sufficient 

 to identify the species. This species appears to be new to Britain. 



Additions to the Copepoda of the Firth of Clyde. 



Scottocheres elongatus (T. and A. Scott), (PI. XIII., figs. 10-21). 



1894. Acontiophorus elongatus, T. and A. Scott, 'Ann. and Mag. 

 Nat. Hist.,' ser. 6, vol. xii. p. 145, PI. IX., figs. 15-20 ; 

 and T. Scott, Twelfth Ann. Rep. Fish. Board, Scot., 

 Part III., p. 261. 



1897. Scottocheres elongatus, W. Giesbrecht, * Zool. Anzeig.,' 

 Nos. 521, 522 (separate copy), p. 6. 



This Copepod was partly described by Thomas and Andrew Scott in 

 1894 from one or two specimens obtained in the Firth of Forth. It was 

 ascribed to Acoritiophorus, Brady, as that was the genus to which it was 

 apparently most closely related. Since that time Dr. Giesbrecht^ the 

 eminent crustaceologist of the Kaples Zoological Station, has made a 

 special study of this family of the Copepoda, and introduced certain 

 necessary changes in the arrangement and nomenclature of the various 

 genera and species comprised in it. One of these changes is the 

 institution of a new genus for this Copepod, viz., Scottocheres — as 

 indicated above. It is interesting to note that Dr. Giesbrecht has dis- 

 covered Scottocheres elongatus in the vicinity of x^aples. Till com- 

 paratively recently this species was known to me only from the Firth of 

 Forth, but I am now able to record it also from the Clyde, a specimen of 

 it having been obtained in the vicinity of Sanda Island. Its discovery 

 in the Clyde enables me to give a fuller description of the species, and 

 also figures showing additional structural details, as follow : — 



An ova-bearing female has been figured by my son, and is represented 

 in fig. 10. This specimen measured almost a millimetre in length, and 

 carried two ovisacs, each apparently containing three large ova. The 

 antennules are comparatively short, and are seventeen-jointed ; but the 

 eighth joint, counting from the base, ought, perhaps, to be reckoned two 

 joints, as an indistinct suture is seen extending partly across it. The last 

 joint is longer than any of the others except the basal joint, and an 

 sesthetask springs from the end of the second-last joint (fig. 11). The 

 antennae are slender and three-jointed, but the last joint is very small and 

 bears a moderately long claw-like spine ; the secondary branches are also 

 very small, and one-jointed (fig. 12). The mandibles are very long and 

 very slender, being about as long as the siphon, which reaches to 

 near the end of the cephalothorax (figs. 13, 14). The maxillae 

 are small and two-branched ; one branch is stout and somewhat conical 

 in shape, the other is small and somewhat cylindrical ; both branches 

 bear three setae, two of the setae of the larger branch being of consider- 

 able length and plumose (fig. 15). The foot-jaws are elongate and 

 slender, and both pairs have moderately long terminal claws ; the anterior 

 pair are two- jointed, but the posterior pair are apparently four-jointed, as 

 shown by the figures (figs. 16, 17). All the four pairs of swimming feet 

 have both branches three-jointed (figs. 18 and 19 represent the first and 

 fourth pairs) ; the fifth pair are broadly elliptical, and bear three terminal 



