698 MESSRS. E. HEEON-ALLEN AND A. EAELAND ON THE 



Discorlina vesicular is Millett, 1898, etc., FM. 1903, p. 702. 



Earland, 1905, FBS. p. 224, pi. xii. figs. 9, 10; pi. xiv. fig. 6. 

 Chapman, 1907, RFV. p. 135. 

 Heron-Allen & Earland, 1913, CI. p. 131. 



5 Stations. 



This species occurs at only a few Stns., but at these, and notably at Stn. IX, it is 

 fairly frequent and attains a size and luxuriance of growth almost equal to the splendid 

 specimens to be found in South Australian shore-sands. With the exception of a 

 record of Brady " Common in the shore-sands of Tamatave, Madagascar," and a few 

 records of pauperate specimens round the British coast, the previously recorded 

 distribution of this species appears to be confined to the Pacific-Australian seas. 



363. Discorbina dimidiata Jones & Parker. 



Discorhina dimidiata Carpenter, Parker, & Jones, 1862, IF. p. 201, fig:. 32 b. 



Parker & Jones, 1865, NAAF. pp. 385 & 422, pi. xix. fig. 9. 

 Chapman, 1907, RFV. p. 136, pi. x. fig. 8. 

 Ileron-Allen & Earland, 1908, etc., SB. 1909, p. 444. 



4 Stations. 



Occurs very rarely, but a few large and quite typical individuals were found at 

 Stns. 8 and 9, almost equal in size to the specimens so abundant in South Australian 

 shore-sands. The presence of this typically Australian species on the African coast 

 is very noteworthy. 



304. Discorbina polystomelloides Parker & Jones. (PL LII. figs. 19-23.) 

 Discorbina polystomelloides Parker & Jones, 1865, NAAF. p. 421, pi. xix. fig. 8. 

 „ Brady, 1884, FC. p. 652, pi. xci. fig. 1. 



" „ Heron-Allen & Earland, 1908, etc., SB. 1911, p. 330. 



12 Stations. 



The original description of this species is not very full or satisfactory. Parker and 

 Jones [ut supra) merely state that it " may be said to be a granulose form of U. rimosa, 

 but it is larger, more symmetrical, and extremely rough, and the chinks between the 

 chambers are partly bridged over, so as to form a rough canal system, as in some of 

 the Polystomellse." 



The description of Discorbina rimosa Parker & Jones, published at the same time, 

 is as follows (P. & J. 1865, NAAF. p. 421, pi. xix. fig. 6) :— "This is smaller than 

 I), vesicularis and close to it and J), elecjans in alliance, somewhat oval in shape ; shell- 

 substance thick, pores large ; septal plane notched for aperture ; chambers very much 

 larger in the newer than in the older part of the shell, and discrete ; and on the upper 

 side several of the newer chambers are separated by chinks. On the under side there 

 are secondary chambers over the umbilicus, perfect, large, and astral, with chinks at 

 their periphery." 



