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Part III. — Eleventh Annual Report 



The male antenna?- are considerably dilated. There is a constriction 

 between the third and fourth joints ; the articulation between these forms a 

 hinge to enable the antenna? to be used for grasping ; the fifth joint is 

 small, and bears a short stout spine on its upper distal angle, while the 

 sixth joint is furnished with a sensory filament. First pair of swimming feet 

 short, the outer branch three-jointed, the inner two-jointed, both, branches 

 of about equal length, the basal joint of the inner branch stouter and 

 rather shorter than the other ; the margins of both joints are fringed with 

 short spiniform seta? ; the last joint bears at its distal extremity a mode- 

 rately short plumose spine, and one short and one long bent subterminal 

 seta ; each of the three joints of the outer branch is armed exteriorly 

 with a subterminal and somewhat stout plumose spine, the second joint 

 carries a moderately long seta on the inner distal angle, while the last 

 joint carries two terminal and one long bent subterminal setae (fig. 24). 

 Inner branches of the third pair scarcely longer than the first two joints 

 of the outer branch, first joint very short ; in the male the first joint 

 bears a long stout setaform appendage, which is at least two and a half 

 times the length of the inner branch ; there is a small seta at the base of 

 the appendage ; the only armature of the second joint — which is somewhat 

 lageniform — consists of two terminal plumose seta?, one being much longer 

 than the other (fig. 27). Inner branches of the fourth pair shorter than 

 the first two joints of the outer branch, first joint very small; the arma- 

 ture of both branches somewhat similar to that of the third pair (female). 

 Fifth pair small, foliaceous • in the female the basal joint bears four long 

 and two short plumose seta? ; the long seta? are arranged as follows : — one 

 on the inner and one on the outer margin near the somewhat truncate 

 extremity, and two of them terminal, one of which is considerably longer 

 than either of the other three ; the two short seta? spring from the inner 

 margin, as shown in the figure (fig. 29) ; the second joint is smaller, 

 obliquely truncate, and provided with five seta?, as shown in the figure. 

 In the male the basal joint is boldly convex, and bears two short plumose 

 terminal seta?, second joint small subovate, furnished with one stout, 

 coarsely plumose, and moderately long terminal seta, and two small seta? on 

 the inner and three on the outer margin (fig. 30). Abdominal segments 

 ornamented with two concentric rows of small prickles — one row near the 

 lower and one near the upper margin, but the last row is not so con- 

 spicuous as the other. The opercular plate has the edge strongly aculeate. 

 Caudal stylets short, somewhat dilated, and provided with two long ter- 

 minal unequal seta?, one being about twice the length of the other, and 

 a few short hairs (fig. 31). 



This species was described by Dr Brady from specimens obtained by 

 Mr Thomas Atthey, amongst gelatinous alga? growing on the roof of the 

 pit-workings of the low main West Cramlington Colliery, near New- 

 castle, in 1868 : so far as I can learn, it was not known to occur any- 

 where else till it was obtained in Loch Morar during our examination of 

 that loch. Specimens were sent to Dr Brady, and he was able to recog- 

 nise them as belonging to the species he had described from the West 

 Cramlington Colliery. 



It may be of interest to note here, that quite recently, when examining 

 some material collected by hand-net in the vicinity of Harelaw Dam, Balerno, 

 near Edinburgh, in August 1890, and which had not been examined pre- 

 viously for want of time, several specimens of this interesting species were 

 observed, thus indicating that its distribution may not be so restricted as 

 had. been supposed. Its occurrence among the gelatinous alga? on the roof of 

 the pit-workings at West Cramlington is very curious and interesting, and 

 opens up questions respecting distribution of species which, like that of 

 the ' toad in the rock/ may not be easily solved. 



