Proceedings of the Roycd Society 
:^>74 
species Myzostoma carpenteri. That on the smaller individual was 
the larger of the two (2 '3 mm.), almost rivalling its host in 
diameter. 
Even the smallest of these seven individuals has fully developed 
ovaries ; but it is only in the largest that the cirri exceed 10 mm. 
in length, and are composed of more than twenty joints. 
This species was taken by the “ Porcupine ” both in the warm 
and in the cold areas. 
5. Antedon eschrichti, Miill. sp. 
H.M.S. “Triton,” 1882. Station 4. Lat. 60° 22' 40" N. and 
60° 31' 15" K, long. 8° 21' W. and 8° 14' W. 327 to 430 fathoms. 
Temp. 31°-5 to 30° F. Stones; mud. 
A small but singularly interesting example of this well-known 
Arctic type. The cirri are small and comparatively delicate, not 
exceeding 20 mm. in length ; and the arm-bases are but slightly 
tubercular. All the arms have been broken either at the second 
(8th) or third syzygy (12th or 13th brachial). 
One can therefore study the appearance presented by the new 
arm-joints in various stages of growth. The lowest and therefore 
oldest of these new joints are most like those of the corresponding 
part of the arm in the adult, ^.e., triangular or very slightly quad- 
rate, but relatively long in proportion to their width. These 
characters, however, do not disaj^pear as they do in the adult, where 
the joints gradually become shorter and shorter, with a markedly 
triangular outline. But throughout the remainder of the restored 
arms the joints are quadrate and relatively long ; while the two lowest 
pinnule-joints show but few traces of the flattening and peculiarities 
of outline wliich are so characteristic of the adult. It is just in these 
characters (besides the smaller size of the third pair of pinnules) that 
Antedon quadrata (No. 7) differs from Ant. eschriehti ; and it is 
therefore to be regarded as a permanently immature form of the 
latter species. 
6. Antedon hystrix, sp. n. 
H.M.S. “Triton,” 1882. Station 4. Lat. 60° 22' 40" N. and 
60° 31' 15" N., long. 8° 21' W. and 8° 14' W. 327 to 430 fathoms. 
Temp. 31° “5 to 30° F. Stones: mud. 
