REPORT ON THE PENNATULIDA. 29 



Colour of the cells of the polyps and zooids light red, and of the stems of the tentacles 

 of the polyps pale red, which colour is occasioned by red calcareous needles. Besides 

 these, colourless needles occur in all uncoloured parts of the rachis, and in the stems of 

 the tentacles at their ends. 



Axis cylindrical, 0"37 mm. 



Habitat. — One single specimen from Station 44, North Atlantic, south of New York, 

 lat. 37° 25' N., long. 71° 40' W. Depth, 1700 fathoms. Bottom temperature, l°-7 C. 

 Grey ooze. May 2, 1873. 



2. Protoptilum, sp. 



A fragment of a Protoptilum differing from Protoptilwn aherrans, (1) by the more 

 intense colour of the cells, (2) by the longer row of undeveloped pol)-ps, (3) by the 

 occurrence of only dorsal and ventral zooids, (4) by the smaller size of the pol}npidom, 

 (5) by the more intense colour of the needles of the stems of the polyps, (6) by the 

 absence of a swelling at the lower part of the rachis. 



The fragment in question consists of a stalk, which has an upper swelling, and a large 

 end-bulb. 



Habitat.— Citation 45, North Atlantic, south of New York, lat. 38° 34' N., long. 

 72° 10' W. Depth, 1240 fathoms. Bottom temperature, 2°-4 C. Mud. May 3, 1873. 



3. Protoptilum, sp. 



A second fragTaent comes nearer to Protoptilum aherrans, and differs from it only in 

 the want of colour of. the needles in the tentacles of the polyps, and in the absence of 

 generative organs in the swelling of the rachis. 



Habitat.— ^tsAion 46, North Atlantic, east of New York, lat. 40° 17' N., long. 66° 

 48' W. Depth, 1350 fathoms. Bottom temperature, 2°-3 C. Mud. May 6, 1873. 



Trichoptilum, u. gen. 



Sea-pens of the family of the Protoptilidse. Polyps with cells, sessile, disposed alter- 

 nately in one single row on each side of the rachis. Cells cylindi'ical, Avith eight strong 

 spines. Zooids dorsal, one to three between the pol}TDs, small, without spines. Axis 

 quadrangular. Calcareous laodies numerous in the cells and tentacles of the pol)-ps, very 

 scarce in the sarcosoma of the rachis, abundant in that of the stalk. 



1. Trichoptilum brunneum, n. sp. (PI. VIII. fig. 31). 



Long and slender. Rachis more than five times the length of the stalk. Length of 

 rachis, 29 mm. of stalk, 5-3 mm. Stalk, with an upper enlargement of I'G mm. and 

 an end-bulb of 2-6 mm. diameter, with .short calcareous needles of 42 to 68 yx, which are 

 very numerous in the upper pai-ts, and diminish in number towards the end-bulb. 



