Dr. T. Scott 071 British Copepoda. 571 



to Jonesiella in general appearance. Antennules (anterior 

 antenna) short and composed of six joints. Antennse (poste- 

 rior antennw) with the outer ramus well developed, three- 

 jointed, middle joint short. Mandibles distinctly two-branched. 

 First pair of thoracic feet with both branches three-jointed, 

 the inner being more elongated than the outer branches; 

 other thoracic feet somewhat similar in structure to tliose of 

 Jonesiella. 



Thompsonula hymnm (I. C. Thompson). 



1889. Jonesiella hyceiia, I. C. Thompson, Proc. Biol. See. Liverpool, 



vol. ui. p. 193, pi. ix. tigs. 1-10. 

 1893. Jonesiella hyarKs, T. Scott, Eleventh F. B. Report, pt. iii. p. 202, 



pi. HI. figs. 1-6. f ' 1' V 



In this species the basal joint of the short six-jointed 

 antennules is veiy stout and comparatively large ; it extends 

 forward, while the remaining joints curve outwards, so that 

 the last three are nearly at right angles to the basal joint. 

 The rostrum, which extends forward between the basal joints 

 of the antennules, reaches to beyond the extremity of these 

 joints. The furcal joints are extremely short, and as the 

 last abdominal segment is tolerably broad, the posterior has 

 an abruptly truncated appearance. 



Further particulars concerning this interesting species will 

 be found in the papers referred to above. 



