. 130 Part I1I.—Twenty-first Annual Report 
moderately rare species, but it has so much the appearance of a 
Seutellidium or a Zaus that it may have been frequently overlooked. 
Thalestris rugocincta, Norm., and Thalestris clausii, Norm., were taken 
in the same gathering with 7’. peltata. 
Genus Westwoodia, Dana (1855), 
Westwoodia nobilis, Baird. 
1845, Arpacticus nodilis, Baird, Trans. Barw. Nat. Club, vol. ii, 
p. 155. 
1880. Westwoodia nobilis, Brady, British Copepoda, vol, ii. 
p. 141, pl. lxiii., figs. 1-13. 
This prettily-coloured Harpactid was observed in the same gathering 
with the Tialestris just mentioned. It seems to be a littoral form, and 
its habitat here agrees with what is stated by Prof. G. 8. Brady and Rev. 
A. M. Norman, but it has also been obtained in water of moderate depth, 
as off Portincross, Firth of Clyde, where it occurred at depths ranging 
from ten to thirty fathoms.* 
] 
LicHOMOLGID. 
Genus Paranthessius, T. Scott, gen. nov. 
Antennules short and seven-jointed. Antenne four-jointed, armed with 
a stout terminal claw. Mandibles and maxille somewhat like those of 
Lichomolgus fucicolus. Anterior maxillipeds small, furnished with 
strongly curved and elongated terminal claws. The first three pairs of 
thoracic feet are similar to those of Lichomolgus, but in the fourth pair the 
inner branches appear to be entirely wanting. Fifth pair rudimentary or 
very small. 
Paranthessius dubius, T. Scott, sp. nov. Pl. vi., figs. 16-24. 
A single male specimen of a somewhat curious Lichomolgus-like 
copepod was obtained in some dredged material sent from the Clyde, and 
collected on June 13, 1899. It has been left unrecorded hitherto in 
expectation that other specimens, especially females, might be found, and 
a more exact knowledge obtained of its structure and affinities. It differs 
in several particulars from any described genus or species at present known 
to me, and I therefore submit the following description of it under the 
name of Paranthessius dubtius. : 
The male in its general outline somewhat resembles Psewdopsyllus 
elongatus, a copepod described in my paper in Part III. of the Twentieth 
Annual Report. The body is elongated and narrow ; the cephalo-thorax 
is composed of five segments, the first is rather broader than the others 
and is considerably longer than the combined lengths of the remaining 
four segments; these four segments, which are sub-equal in length, 
become gradually narrower, so that the last is narrower than the first 
segment of the abdomen. The first abdominal segment is considerably 
dilated, but the remaining segments are short and narrow ; the furcal 
plates, which are moderately broad, are aboutas longas the last two segments 
of the abdomen (fig. 16). The length of the specimen is fully 2 mm. 
_ (about +4, of an inch). 
The antennules (fig. 17) are short and moderately stout and composed 
of seven joints, the second joint is the largest, the third and fourth are 
* British Copepoda, vol, ii., p. 142 (1880). 
