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Part III. — Eighteenth Annual Report 



drawing (fig. 38) was obtained was captured in the Firth of Clyde in 

 25-30 fathoms, November 1899. A second specimen, exhibiting even a 

 closer resemblance to the figure, was obtained on a common dab taken by 

 the " Garland " at Station VII. in the Moray Firth on January 24th of the 

 piesent year (1900). 



This species is moderately robust ; the first thoracic segment is very 

 short ; the second is of moderate size, and has on each side a slightly 

 elevated and broadly rounded knob — "annulo secundo duobus tuberculis 

 humeralibus praedito magnis." * The posterior portion of the thorax is 

 more or less distinctly constricted, so that this portion of the thorax 

 appears as if it were divided into two slightly unequal parts. The thoracic 

 limbs are more rudimentary than those of Chondr acanthus cornutus ; 

 in that species the second pair are distinctly bifid, but in the present 

 form they are not so, or they show at most the merest trace of bifurca- 

 tion, agreeing in this respect also very closely with Kroyer's description — 

 " Membra annuli thoracici primi et secundi latiora quam longiora semilu- 

 naria, haud furcata, posterius par priori multo majus." The posterio- 

 lateral projections of the thorax are comparatively short and stout ; the 

 abdomen is very short and composed of two segments. 



The specimen represented by the drawung is about 5mm., exclusive of 

 the ovisacs, which are about the same length, giving a total length of 

 about 10mm. 



The male is very small ; one which I measured was only 0*6 5mm. 

 (scarcely one-thirty-eighth of an inch) in length. 



Chondr acanthus ornatus, sp. n. 



I have recently obtained on the gills of specimens of the spotted 

 dragonet, Callionymus maculatus, a Chondracanthus-like copepod, which 

 appears so far to be undescribed. The female of this copepod viewed 

 from above has a general outline closely similar to that of an equilateral 

 triangle, the bluntly-rounded head forming the apex and the truncate 

 posterior end the base ; the front of the head is indistinctly tridobed, one 

 bluntly-rounded lobe being in the centre, and projecting slightly in front 

 of the two lateral lobes, which are also bluntly rounded ; the neck con- 

 necting the head with the thorax is very short ; along each side of the 

 thorax (forming the sides of the triangle) there are three or four more or 

 less distinct tuberclest, and a series of three similar tubercles extends 

 along the middle of the dorsum ; the posterior tubercle of the middle 

 series stands well up, but each of the other two stands at a slightly lower 

 elevation than the one immediately behind ; the abdomen is exceedingly 

 small and inconspicuous. The ovisacs are of moderate length and stout- 

 ness, like those of Chondr acanthus Umandoe. 



The length of the more typical of my female specimens is as follows : 

 From forehead to the posterior end of body, 5mm. (one-fifth of an inch); from 

 forehead to the end of the longest of the two ovisacs, ll'Smm. (nearly half 

 an inch) ; the width of the thorax at the posterior end is just a little over 

 5 mm., so that the body of the animal, as I have already said, has a 

 general outline closely similar to that of an equilateral triangle. 



The male is very small ; it scarcely reaches to 0'6mm. (^ of an inch) 

 in length. I have not had time to get drawings of this interesting 

 species prepared, but it has such a characteristic form that the descrip- 

 tion of the female I have given, together with the habitat of the species, 

 should facilitate its identification. I have obtained the species on the 



* Kroyer, Naturh. Tidsskr., R. III., Bd. 2, p. 330 (1864). 



f The arrangement and position of these lateral tubercles seems to vary slightly in 

 different specimens ; the description refers to the general appearance as seen from above. 



