400 



Part III. — Eighteenth Annual Report 



variety of that species. It differs from the typical Asterocheres echinicola 

 in having the caudal segments rather shorter than the anal segment, while 

 in typical specimens these are slightly longer than that segment. 

 The general outline of the cephalothorax, and especially the outline 

 of the posterior margin of the third segment, seem also to be slightly 

 different, as shown by the drawing (fig. 33). Moreover, the outer lobe of 

 the maxillae is also apparently somewhat shorter than that of the same 

 appendages in Asterocheres echinicola, but whether such differences are 

 constant seems somewhat doubtful. 



A species of Asterocheres described by Dr. Giesbrecht, of Naples, under 

 the name of Asterocheres suberites, seems to have a habitat similar to this 

 Loch Fyne form, and it also agrees with the same form in having the 

 caudal segments shorter than the anal segment ; indeed the difference in the 

 length of the caudal segments appears to constitute one of the principal 

 points of distinction between Asterocheres echinicola (Norman) and 

 Asterocheres suberites (Giesbrecht). Notwithstanding the points of agree- 

 ment observed between this Clyde copepod and Giesbrecht's A. suberites, 

 I prefer for the present at least to ascribe it to the A. echinicola, Norman. 

 It may also be noted that Asterocheres boecki (G. S. Brady) was occasion- 

 ally obtained in the water-passages of Suberites in company with the 

 A. (?) echinicola. 



Rhynchomyzon purpurocinctum (T. Scott). 



1893. Cyclopicera purpurocinctum, T. Scott, Eleventh Ann. Report 

 Fish. Board of Scot. (III.), p. 209, PL III., figs. 29-40. 



This species, which has already been recorded from one or two 

 places on the East Coast of Scotland, has only recently, and for the 

 first time, been observed in the Clyde district. It occurred in the 

 washings of dredged materials (weed, gravel, sand, etc.) collected in 

 the vicinity of Otter Spit, Upper Loch Fyne, on Januaiy x2th, 1899, at a 

 depth of about 8 to 15 fathoms. The occurrence of the species here 

 would seem to indicate that though it may be, and probably is, a scarce 

 one, it may be more or less generally distributed around our shores. The 

 species is readily distinguished not only by its general form, but by the 

 fact that it is adorned by a dark purple-coloured band extending across the 

 thorax, and it is worth noting in regard to this band that a lengthened 

 immersion in methylated spirits appears to have had little effect on it. 

 Usually the spirit extracts the colouring matter very quickly from these 

 microforms, but it would appear that in this case the purple pigment is of a 

 more permanent character than that generally observed in the colours of 

 copepoda. 

 * 



Artotrogus orbicularis, Boeck. 



1859. Artotrogus orbicularis, Boeck, Forh. Vid.-Selsk.,Christiania, 

 p. 2. PL I. 



One specimen, about one millimetre in length and 0*78 millimetre in 

 breadth, was obtained amongst some washings of material dredged on 

 Tarbert Bank, Loch Fyne, on the 28th October last (1899). This is the 

 second specimen of this rare species from the same locality.* I. C. 

 Thompson has recorded this species from the Liverpool Bay district,f but 

 Tarbert Bank, Lower Loch Fyne. is the only Scottish locality I know of 

 where Artotrogus orbicularis has been obtained. 



* Sixteenth Ann. Report Fish. Board of Scot. (III.), p. 272, PI. XIV., figs. 12-21 (1898). 

 f Trans. Lit. and Phil. Soc, Liverpool, vol. viii., p. 37. 



