of the Fishery Board for Scotland. 



323 



Canthocamptus cuspidatus, Schmeil (PI. IX., figs. 21 and 22). 



1893. Canthocamptus cuspidatus, Schmeil, ' Gopepodes des Rhati- 

 kon-Gebirges ' (Abhandl. d. Naturf, Gesellschaft zu 

 Halle, Bd. xix.), p. 36, taf. iv. (separate copy). 



Habitat. — Loch Fad, Bute ; Loch Venuachar, Perthshire ; Loch of 

 Tingwall (Scalloway) ; and Loch of Brough (Bressay), Shetland. 



Remarks. — During the past year a fresh- water Harpactid was obtained 

 at Loch Fad in Bute ; sometime afterwards this was identified as similar 

 to a copepod that had been observed in Loch Vennachar, and which, in 

 my paper on the ' Inland Waters of Scotland,' published in Part III. of 

 the Fourteenth Annual Report of the Fishery Board, had been ascribed 

 to Attheijella Macandrewce, T. and A. Scott. At the time the Loch 

 Vennachar specimens were examined certain differences were noticed 

 between them and the typical Attheyella Macandrewce from Loch na Chaite 

 on Ben Lawers; but it was considered that these differences might be 

 due to the difference in habitat, and that the Loch Vennachar copepod 

 might be only a variety of that from Ben Lawers. The recent discovery, 

 however, of the species at Loch Fad, has led to its re-examination ; and 

 I have also recently had an opportunity of consulting a work by Dr 

 Otto Schmeil on some Copepoda collected by Dr F. Zschokke in the 

 Rhaetian Alps between Austria and Switzerland ; and from the additional 

 information thus obtained, I am now satisfied that the Loch Fad species 

 is identical with that described by Dr Schmeil as Canthocamptus cuspi- 

 datus, from the collections of Dr F. Zschokke referred to above. 



It may also be mentioned that, so far as I can judge, the Ben Lawers 

 Attheyella Macandrewce seems to be identical with Canthocamptus rhce- 

 ticus, another of the species found by Dr Schmeil in the collections from 

 the Rhsetian Alps, and described by him in the same work with the others.* 



The disparity between Canthocamptus rhceticus and Canthocamptus 

 cuspidatus is not at first sight very apparent, and the two are evidently 

 closely allied species. When, however, they are dissected and examined 

 by the aid of the microscope, several quite distinct, though minute, 

 differences become visible, of which the following seem to be the most 

 important. The mandible-palp in Canthocamptus rhceticus is only 

 about half the size of that of Canthocamptus cuspidatus. The 

 proximal joint of the inner branches of the first thoracic feet is pro- 

 portionally considerably shorter than the same joint in Canthocamptus 

 cuspidatus, and the entire inner and outer branches are also proportion- 

 ally shorter. In the fifth pair the produced inner portion of the basal 

 joint is narrower in Canthocamptus rhceticus, and the secondary joint is 

 sub-quadrate in form • in Canthocamptus cuspidatus the form of the 

 secondary joint is broadly sub-ovate ; the difference in the armature of 

 both basal and secondary joints is also very marked 



Several of the Loch Fad specimens of Canthocamptus cuspidatus carried 

 ova, and the ovisacs were in every case small, and contained very few 

 but comparatively large ova : so different was the appearance of the 

 ovisacs, that those of the Loch Fad specimen which carried ova could be 

 distinguished by t>hat character alone. Figures of the first and fifth 

 thoracic feet (female) are given on PI. IV., figs. 21 and 22. 



Canthocamptus inornatus, sp. n. (PI. IX., figs. 1-12). 



Description of the Female. — Length about '85 (/o tn °f an lncn )- 



* Copepodes des Bhdtikon-Gebirges, p. 23, taf. ii. (As Canthocamptus rhceticus, 

 Schmeil, was published in 1893, and Attheyella Macandrewce was not published 

 till the following year, this name must give place to the other. ) 



