ENHYDROSOMA. 97 
nearly equal size, but short, being scarcely longer than 
the width of the thorax; the margins of all the joints 
of the outer branches are fringed with spine-like seta, 
and the apical spines are Jarge and strong. The fifth 
pair, in the female (fig. 11), has the basal joint well 
developed and forming a large internal segment, which 
bears five marginal sete; outer branch subovate, 
having four large and two small sete; the margins of 
both joints finely ciliated; the tail-segments have at 
the apex one stout seta about equal in length to four 
of the abdominal joints, and on the lateral margins are 
also three or four minute sete. Length, g'snd of an 
inch (1:1 mm.). 
This is a very distinct and at the same time one of 
the least common of British species. I for a long 
time knew it only from two specimens, one found on 
a Sponge in Westport Bay, and one taken amongst 
Alge at St. Mary’s, Scilly; but more recently I have 
found several specimens in a collection of Copepoda 
washed from the roots of Alge gathered in Round- 
stone Bay. 
Genus 21. Enuyprosoma, Boeck. 
(Boeck, Nye Slegter og Arter af Saltvands-Copepoder, 1872.) 
Body subcylindrical ; first pair of antenne short and 
stout, 5-jointed; second pair nearly as large as the 
first, 2-jointed, secondary branch small, 1-jointed; 
VOL. II. G 
