TUBULIPORID.E : ALECTO. 281 



The Alecto granulata of Milne-Edwards is a fossil, but I can dis- 

 cover no difference between it and our recent species. 



2. A. MAJOR, cells liserial or triserial, immersed, smooth. 

 Rev. D. Landsborough. 



Plate XLIX. Fig. 3, 4. 



Tubiilipora repens ? S. V. Wood in Ann. and Mag. N. Hist. xiii. 14. 



Hah. — On stones and old bivalve shells from deep water, not rare. 



Polypidom calcareous, branched, very closely adherent, the basis 

 somewhat dilated or effused, white and vitreous, scored with faint 

 lines longitudinally, marking the septa of the tubular cells, which are 

 in one, two or three series, entirely immersed in the crust, except 

 towards the extremity which is suddenly raised into a short cylindri- 

 cal tube with a circular plain aperture. 



This is a much stouter species than the preceding, and the surface 

 is scarcely if at all granulous. It is very irregularly branched, the 

 branches being almost always expanded or clavate at their ends ; and 

 hence young or unbranched specimens have the figure of a tear that 

 trickles slowly down the cheek, — an apt comparison, which I steal 

 from my friend the Rev. D. Landsborough. It adheres very firmly 

 to its foreign basis, for the basal portion of the polypidom itself is 

 somewhat effused, so that the cells lie, as it were, upon and in this 

 crust, showing themselves only by their raised tubular apertures, 

 which open usually two or three together in a cross line, although in 

 some parts there is one only. 



I cannot reconcile this species with any described by Milne-Ed- 

 wards. It was first sent to me by the Rev. D. Landsborough under 

 the name of Alecto dichotoma 1 I then received several specimens 

 from W. Thompson, Esq., dredged off Sana Island ; and subsequently 

 Mr. Couch sent it as his Tubulipora trahens, at the same time re- 

 marking that the specimens were not good representatives of that 

 species. Whether it is a state of T. trahens or not I will not decide, 

 but the two appear to me to be specifically distinct. The A. major 

 differs from A. granulata in its superior stoutness and breadth, in its 

 firmer adherence to its site, in the less elevation of the ends of its 

 tubes, and in the want of granules on the surface of the polypidom. 

 These characters may vindicate its specific rank. See page 82. 



3. A. DiLATANs, iranched, branches dilated at the ends ; 

 cells multiserial, the parietes granidous. W, Thompson. 



