238 THE VOYAGE OF H.M.S. CHALLENGER. 
Tertiary beds of the Continent may really belong to this genus. Meneghini has indeed 
suggested that two forms of joint found in the Italian Tertiaries are those of Bathycrinus;' 
but there is no evidence either for or against this idea. For the lower stem-joints of 
Bathycrinus are indistinguishable from the non-cirriferous jomts of Rhizocrinus, though 
the differences between the immature joints of the upper part of the stem may be readily 
recognised in the two genera. 
Key TO THE SPECIES OF BATHYCRINUS HEREIN DESCRIBED. 
I. The lower part of the radial funnel much constricted, é : . 1. Campbellianus. 
II. The radial funnel slopes uniformly downwards from the upper to the fo er edge. 
a. Calyx constricted at the basiradial suture. Basal ring scarcely wider 
above than below. Arm-joints smooth, 5 ‘ . 2. Aldrichianus. 
b. The slope of the radials is continued on to the basal ring, sah? is W He 
above than below. Arm-joints overlap, . : : : . 3. Gracilis. 
1, Bathycrinus campbellianus, n. sp. (Pl. VIIa. figs. 22, 23; Pl. VIII.; woodcut, fig. 15). 
Bathycrinus aldrichianus, Wyv. Thoms. (pars), Journ. Linn. Soc. Lond. (Zool.), (1876), vol. xiii., 
1878, pp. 47-51, fig. 1; The Atlantic, 1877, vol. ii. pp. 92-95, fig. 23. 
Dimensions. 
Total length of specimen, without stem, . é . : . 982°00 mm. 
Greatest height of radial funnel, . : 5 : ‘ : SON 
Greatest diameter, ; ‘ ji : ‘ : : 3008s; 
Least diameter, . : 4 : : : ; : 7A0) 55 
Length of second radial, . : - : : ¢ 3 IGS5) Ms 
Length of third radial, : : 5 : : ‘ Talo ee 
Stem and basals unknown. 
Description of an Individual.—The radial funnel widens slightly from below upwards 
to just beneath its equator, where it expands considerably, owing to the dorsal surface of 
the radials suddenly becoming much more convex. The rim of the funnel is thus drawn 
out into five curved edges in which the second radials rest. They are trapezoidal in 
form, widen from below upwards, and have a strong medio-dorsal convexity which starts 
from the whole width of the lower edge and narrows rapidly till just beneath the dorsal 
edge, whence it is continued on the axillary. The lateral portions of the surfaces of both 
joints are flattened. The axillaries are shorter than the second radials, but wide and 
barely pentagonal in form, with a medio-dorsal ridge which forks at its proximal end and 
is continued on to the arm-bases, where it soon disappears. The flattened lateral portions 
1 Processi. Verbali, Soc. Tose. di Sci. Nat., 7 Luglio 1878, p. xxxii. 
