256 llev. T. Hincks's Catalogue of Zoophytes 



Laminarian zone, especially on Halidrys siliquosa, large masses 

 of which are often thickly covered with its graceful plumes. It 

 occurs in great profusion and beauty under the rocky shores of 

 Salcombe Bay, and of Berry Head, Torbay. The plumes some- 

 times attain a great size. On specimens procured at Exmouth 

 they are 2^ inches in height, and bear about a dozen of the 

 pod-like cases [corbulce of Allman), which protect the reproduc- 

 tive capsules, set along the rachis. In other examples the plumes 

 are of great width (three-quarters of an inch across), beautifully 

 curved, and also bearing the corbulse in a single line upon the 

 main stem. 



The tall, slender and branched variety, figured by Dr. John- 

 ston {pi. 24. fig. 1), occurs on the South-Devon coast. 



3. P. tubulifera, n, sp. PI. YII. figs. 1, 2. 

 Plumose, simple, pinnae alternate. Cells cup-shaped, slender, 

 elongate, not expanded above; margin minutely denticu- 

 late; a large ear-like process on each side, springing from 

 the rachis on a level with the rim, and a projecting process in 

 front, supporting a small cup-like cell, with a crescentic open- 

 ing at the extremity. 



On Gorgonia verrucosa, from deep water, coast of Cornwall, 

 The plumes of this species are of a delicate habit, and about 

 an inch, or a little more, in height ; they bear a strong general 

 resemblance to those of P. cristata, from which, however, they 

 are readily distinguished on examination. The cells of P. tubu- 

 lifera are slender, somewhat elongate, gracefully incurved in 

 front, and are not expanded above like these of P. cristata, which 

 are shorter and have a very patulous opening. The marginal 

 denticulation is delicate, and very much finer than in the latter 

 species, in which the rim is cut into very lai*ge and prominent 

 spines, which are somewhat everted. The lateral processes, 

 which in P. cristata are very slightly developed and inconspicuous, 

 constitute a striking feature in the present species, and give a 

 very peculiar appearance to the pinnae when viewed in front; 

 and instead of the short and stout spine which in P. cristata 

 projects in front of the cell, we have in P. tubulifera an anterior 

 process which supports a cup-like body with a crescentic orifice 

 at the top. 



There are also diff'erences between the two species in the 

 structure of the main stems, the joints of which are dissimilar. 



The variety of P. cristata mentioned by Dr. Johnston as 

 " imitating the habit of P. pennatula," and which is also noticed 

 by Mr. Couch, is probably identical with this species ; but the 

 figure of it in the 'British Zoophytes' (p. 94, fig. 16) does not 

 give any true idea of P. tubulifera. 



