of the Fishery Board for Scotland. 469 



a good deal of fibrous matter, collected in Loch Fyne on September 29th, 

 1899, over eighty specimens of Monstrilla were obtained, while in 

 another, collected on the 28th of November, twenty-seven specimens 

 were found.* All these specimens, which appear to belong to the one 

 species, I have recorded as Monstrilla (?) dance, Claparede.f It may be 

 remarked, however, that Dr. Giesbrecht seems to think that the species 

 described by Claparede is not a Monstrilla, but should be placed in the 

 genus Thaumaleus.% 



In a tow-net gathering collected in Lerwick Harbour in October 

 last year (1900), a specimen belonging to the group of copepodss under 

 consideration was obtained, but owing to some doubt concerning its 

 identification it was left over for further examination. I now find that 

 this specimen belongs to the genus Thaumaleus of Kroyer, and a short 

 description of it follows that of Monstrilla. 



But besides the specimens alluded to above, others have been obtained 

 in the Moray Firth, which have still to be examined ; but the study of 

 the group is a somewhat difficult one, and the more so as some of the 

 descriptions and figures of the earlier writers are sometimes wanting in 

 that fulness necessary for certain identification. 



Monstrilla longiremis, Giesb. PI. XXV., figs. 3, 4. 



1892. Monstrilla longiremis, Giesbrecht, Pelagischen Copepoden 

 des Golfes von Neapel, p. 589, pi. 46, figs. 10, 14, 22, 37, 

 41. 



The Monstrilla which I now record from the Firth of Forth was 

 obtained in a bottom tow-net gathering collected at Station V. (to the 

 west of May Island) on July 24th, 1901. The antennules (first antennae) 

 are moderately. elongated, but with the exception of an articulation near 

 the base, the joints are very indistinct ; the setae were imperfect, and did 

 not show the branched structure exhibited in Dr. Giesbrecht's figure of 

 the antennule of Monstrilla longiremis. In the general form of the body 

 and of the thoracic appendages the Forth specimen agrees very well with 

 the species named. The abdomen consists of four segments, but the 

 articulation between the first and second is not very marked, the third 

 and fourth are short and distinct. The furca are of moderate size, and 

 are each provided with five setae as shown in the figure ; no trace of a 

 sixth seta could be observed. 



The fifth feet consist each of a short, one-jointed sub- cylindrical branch, 

 the proximal half of which is somewhat delated interiorly ; each branch is 

 furnished with three apical setae, the inner one being much shorter than 

 the other two, and a fourth seta springs from the inner margin as shown 

 in the figure. 



From these descriptive notes on this specimen from the Firth of Forth 

 there seems to be little doubt that it is identical with the species 

 described by Dr. Giesbrecht under the name of Monstrilla longiremis. The 

 Forth specimen certainly does not show the branching setae exhibited in 

 Dr. Giesbrecht's figure ; but this is not very surprising when it is remem- 

 bered how delicate these long branching setae are, and the friction they 

 may be subjected to while in the tow-net. The specimen I have described 

 is a female ; no male was observed. 



* Eighteenth Annual Report of the Fishery Board for Scotland, Part III., pp. 398-99, 

 pi. xiii., figs. 15-20 (1890). 



f This species has also recently been observed in a gathering from the Firth of Forth 

 collected at Station V. in 1901. 



X Pelagischen Copepoden des Golfes von Neapel, p. 578 et seq. 



