140 TANAIDA. 
extremities of all the joints furnished with a few hairs. 
The lower antenne are four (? five) jointed and slender. 
The second pair of legs are slender, and longer than the 
following pair, with the terminal finger long, very 
slender, and slightly bent. The third and fourth pair of 
legs are very short, and the three posterior pairs longer 
and stronger. The tail nearly occupies one-third of the 
whole length of the animal, the six segments of which it 
is composed being distinct; the five basal ones trans- 
verse, and the terminal one rounded at the extremity, 
which is furnished with a pair of biramose biarticulated 
filiform appendages, slightly hairy at the extremity of 
the joints. 
The first specimen of this species that we obtained 
we dredged in Plymouth Sound. It was very small, and 
possessed but six segments to the pereion, and conse- 
quently wanted one pair of legs. We therefore as- 
sumed it to have been that of a very young animal. 
We have since, from our valued correspondent Mr. 
Edward, of Banff, obtained two others of larger size, 
and with the normal complement of limbs, all the other 
features being persistent, a circumstance that induces us 
to believe that our description represents the character of 
an adult animal. 
We are compelled to adopt this conclusion, from its 
difference from Tanais, its nearest ally, both in the form 
of the second pair of gnathopoda, the number of 
pleopoda developed as swimming appendages, and the 
biramose condition of the posterior pair of pleopoda. 
