145 



Florida, determined by Smitt as M. Lacroixi, I must dispute the correctness of 

 Smitt's determination. The unpaired swelling mentioned before, which is found 

 in the proximal end of some zooecia in M. Lacroixi Aud. S Smitt^ explains 

 as ooecia, which have been placed in an inverted position by Savigny's artist 

 (>drawer«); but there is, I think, no reason to doubt the correctness of the 

 figure. 



Membranipora limosa Waters. 

 Journ. Linnean Soc, Zoology, Vol. XXXI, 1909, p. 140, PI. 12, figs. 1—5. 



(PI. XXII, figs. 5 a-5 c). 



The zooecia, which are separated by distinct (in fresh colonies brown) sutures, 

 are rather long, generally hexagonally rectangular with a curved distal edge. The 

 narrow aperture, which is half as broad and a little more than half as long as 

 the frontal wall, is provided with a semicircular oral valve. The whole of the 

 calcified part of the frontal wall is formed by a cryptocyst, in which we can 

 distinguish between a broad raised marginal portion furnished with parallel series 

 of more or less coalesced tubercles, and of a depressed median part, the distal 

 margin of which is armed with a little process of varying shape, most often 

 bifurcate, sometimes almost fan-shaped with a number of small projecting teeth. 

 The obliquely ascending distal wall, the triangular basal part of which may be 

 split into a distal and a proximal half after treatment with Eau de Javelle, has 

 in its inner part two (more seldom three), fine, slender, erect, somewhat curved 

 calcareous rods, bent at the end like hooks, which project into the proximal part 

 of the distal zooecium and have the hooks directed away from the frontal wall. 

 Each distal wall has in its inner, more horizontal part inside the posterior margin 

 6 — 7 uniporous rosette-plates or a smaller number of plates, of which some are 

 multiporous. The distal half of each lateral wall has generally 2 (rarely a single) 

 rosette-plates with 2 (1) — 6 pores. 



The colonies unjointed, slender, richly branched, with bifurcate branches 

 which bear from 4—5 rows of zooecia. The number of zooecia in the separate 

 rows is from 4 — 14. 



The Formosa-channel, 30 fath. (Suensson), Nagasaki (Suensson). 



As M. membranacea L. must be regarded as the type of the above characterized 

 genus, and the name Membranipora ought therefore in future to be used only in 

 this more restricted sense, we shall want a name to designate all such species 

 as cannot be referred to particular genera. As such a temporary name I propose 

 » Membraniporina < . 



> 98, PI. 10, fig. 9.2. ' 103, p. 18. 



10 



