369 
of Edinhurgh, Session 1883-84. 
continued, thongh less marked, on to tlie later joints. The next 
following pinnules are altogether smaller, consisting of hut a few 
slender joints. 
Disc 5 mm. in diameter, thickly covered with numerous small 
plates, those at the sides of the ambulacra being rather more regu- 
larly arranged than the rest. 
Colour, in spirit, brownish- white or greenish- white. 
H.M.S. “Porcupine,” 1870. Station 17a. Lat. 39° 39' PT., 
long. 9° 39' W. 740 fathoms. Temp. 49°*3 P. 
Ten mutilated specimens. 
Remarks, — Nearly all the individuals obtained had the arms 
broken at the syzygy in the third joint beyond the radial axillaries j 
and it is therefore quite possible that the epizygal of this joint 
might sometimes have been a distichal axillary. In one example, at 
any rate, there are two distichal series, each consisting of two joints, 
the second of which is axillary. This species, therefore, seems to 
be dimorphic like Actinometra pidchella, and to constitute another 
exception to the general rule that ten-armed types are sharply 
distinguished from those in which the primary arms divide. The 
length and spiny character of its cirri, and the peculiarities of its 
pinnules, readily distinguish it from all the species of Antedon hitherto 
described. But it has many points of resemblance to some of those 
dredged by the “ Blake ” in the Caribbean Sea. It is a type of 
some interest for two reasons : it is the only European Comatida 
which is in the condition of the so called recent Cystid, Hiyponome 
sarsiij i.e., with a plated disc and the ambulacra converted into 
tunnels by the folding down of the plates at their sides ; and it is 
the only European Antedon with more than ten arms. 
11. Actinometra pidchella, Pourtales, sp. 
Antedon pidchella, Pourtales, 1878. 
Actinometra y)ulchella, P. H. Carpenter, 1881. 
H.M.S. “Porcupine,” 1870. Station 31. Lat. 35° 56' N., 
long. 7° 6' W. 477 fathoms. Temp. 50° '5 E. Clay. 
One mutilated specimen. 
Remarks. — I cannot distinguish this form from the smoother 
variety of that singularly protean species. Act. pidchellaj of the 
