494 W. WILLIAMSON AND C. D. SOAR ON BRITISH HYDRACARINA. : 



Lebertia celtica Sig Thor. 

 (Sub-gen. Lebertia.) 



1911. Lebertia fimbriata Halbert, Proc. Irish Ac, xxxi. (39i) 



22, plate iii. fig. 31. 

 1911. L. celtica Sig Thor, Zool. Anz., xxxviii. 330. 



Two specimens were taken at Clare Island and recorded as 

 fimbriata. From the short note and figure accompanying the 

 record Sig Thor came to the conclusion that these were sufficiently 

 distinctive in character to warrant a new species, L. celtica. At 

 first, Thor's new species did not seem to be well grounded, and 

 fimbriata var. celtica appeared to be better able to meet require- 

 ments. Careful examination of the types, however, leads to the 

 rejection of a mere variety in favour of celtica n.sp. In support 

 of this may be cited the elongate body form and relatively 

 contracted epimera, and the skin externally smooth but with 

 traces of ridges, either suppressed or of a rudimentary type. 



The body is about 0*9 mm. long and 0*6 mm. broad. The 

 noticeable feature is the evenness of the sides, so that the body 

 is of about the same width throughout. The posterior end is 

 rounded, while the anterior end has a triple indentation, viz. one 

 at each of the corners and one between the antenniform bristles. 

 The colour is a golden brown, with dark patches on the dorsum. 

 Legs and palpi are greyish. Gland pores are arranged in four 

 rows on the dorsum ; each pore has a diminutive guard hair, and 

 is protected by a strong ring. The capitulum measures about 

 0*22 mm. in length, and the mandibles about 0*25 mm. 



At present details as to the capitulum are not available, but 

 these will no doubt become so after further dissections of the 

 type have been made. The palpi are thinner than the first pair 

 of legs, and measure about 0*27 mm. in length. The armature 

 of bristles is as follows : on the extensor surface of the first 

 segment one bristle, and on that of the second segment three 

 short and two long ones at the distal end. The usual long 

 bristle is to be found on the flexor surface. The third segment 

 has the distal extremity rather stouter than is to be found in 

 fimbriata. The five bristles on the inner side occupy practically 

 typical positions, but the posterior one of the five appears to be 

 much longer than the corresponding one of fimbriata. The flexor 

 surface of the fourth segment is almost straight, and has only 



