120 REPORT — 1884. 



this Diachoris BusJcii.' It is very evident tbat the tubular processes 

 cannot be relied upon as generic guides ; both in the genus CJwrizopora 

 and also in Diachoris as now understood these tubular processes vary 

 considerably, as bas already been pointed out by Mr. Waters in the de- 

 scription of the species D. patellaria, var multijuncta (Bry. Bay Nap.). 



111. Ciiokizofoea Bro.vgxiaktii, Aud. = Lepralia ibid. Busk, ' Crag 



Poly.' 40, pi. vi. fi°r. i. ; Manzoni, ' Bry. Foss. Ital.' 2nd cont. 7, 



pi. ii. fig. 9 = Mollia tuberculata and Brongniartii, D'Orb. 



' Pal. Franc. Terr. Cret.' = ? Reptescharallinella rliomboidalis, 



D'Orb. = Lepralia capitata, Rss. 'Bry. d. Ost.-ung.' 21, pi. iv. 



fig. 7. 



Mange. — Coralline Crag; Pliocene, Volterraand Castrocaro (Manzoni); 



Austro-Hungarian Miocene (Reuss). Living, widely distributed in Brit. 



seas. 



Family MicROrORELLiD^;. 



Genus Monoporella. 



General character. — Zocecia destitute of a membranous area or 

 aperture, and of raised margins ; orifice arched above, with the lower lip 

 entire ; no special pores. 



This group is formed for species with a Microporellidan orifice, but 

 destitute of tbe median pox-e, which is so striking a character of tbe 

 genus Microporella. It is difficult to believe that this structure has 

 no special significance ; it is afc least a much better clue to affinity than 

 mode of growth. If this be so, the Microporellidan form from which it 

 is absent may well be set apart as a distinct group. 1 



Family XII. Moxoporellidje. 

 Monoporella, Ilincks. 



Provisionally at least it will be better to keep the genus Monoporella 

 apart from the Microporellida3. If (as seems probable) the special pore 

 of the latter is represented by the oral sinus of the Myriozoida?, Micro- 

 porella will have closer affinity with such forms as Schizoporella than 

 with the present. 



As yet the species of Monoporella described are but few, and we 

 have hardly material for a thorough study of the type. — •' Ann. & Mag. 

 Nat. Hist.' ser. 5 vol. ix., p. 123. 



M. lepida "1 



M. nodulifera VAnn. & Mag. Nat. Hist.,' Feb. 1882, Hincks. 



M. albicans J 



112. Monoporella crassicaules, Waters, ' Quart. Jour. Geol. Soc' 



vol. xxxviii., p. 270, pi. viii. fig. 23. 



113. Monoporella crassatixa, Waters, ' Quart. Jour. Geol. Soc' 



vol. xxxviii., p. 270. pi. viii. fig. 23. 



114. Monoporella hebetata, Waters, 'Quart. Jour. Geol. Soc' vol. 



xxxviii., p. 271, pl.vii. fig. 11. 



1 Smitt's genus Escliaripora (as far as I understand it) is founded for Micro- 

 porellidan forms with more than a single pore. But the physiological significance is 

 the same, whether there be one or many, and the distinction seems to be unimpor- 

 tant ; so also are differences in the shape of the pore. — Ann. ,)'• Mag. Nat. Hist. 

 July, 1881. 



