458 Mr. G. Brook on 7\eio Species of 



meter, cylindrical. Lateral corallites on the distal 5 centira. 

 of a branch, thin, ascending, tubular ; cup deep ; septa scarcely 

 recognizable; length 4 to 5'5 millim., diameter 2 millim., 

 with smaller and subimmersed corallites between. Below^ 

 the distal 5 centim. all the corallites extend at right angles, 

 and none are over 2 milKm. long, and differ from those of 

 M. rohusta in similar situations in the thinner wall, the 

 absence of dimidiate corallites, and the lack of a recognizable 

 star. 



Great Barrier Reef (SaviUe-Kent) . 



Madrepora Guppyi. 



Corallum broad, flattened, cespitose from a broad base. 

 Central branches simple or subsimple, conical, erect, 2 to 2*5 

 centim. thick at the base, 4 to 6-5 centim. long, regularly 

 tapering and rather distant, apices often 4 centim. apart. 

 Axial corallites 3*5 to 5 millim. diameter. Lateral corallites 

 small, very crowded and spreading, subequal, usually thin- 

 walled, often a little compressed, half-tubular or gutter- 

 shaped, with a rounded apex ; length 1"5 to 2 millim., dia- 

 meter 1*2 to 1*5 millim. Star not well developed. 



bolomon Islands {Dr. Quppy), 



Madrepora irregularis. 



Madrepora alces, Briiggemann (uon Dana), Phil. Trans, vol. clxviii. 

 p. 576. 



Corallum consisting of alciform plates with marginal erect 

 digitiform acuminate branches or of short plate-like clusters 

 of incipient branchlets from a narrow base. Proliferous 

 clusters very variable in diameter, up to 2 centim., but not 

 over I'd centim. long, unless forming branches. Apical 

 corallites cylindrical, 2 millim. diameter. Lateral corallites 

 dimidiate or labellate ; wall thin but firm^ very unequal in 

 length, the more prominent are about 1*3 millim. diameter 

 and proliferous. 



Eodriguez (types) ; Macclesfield Bank, 7 to 8 fathoms 

 {H.3L8. 'Penguin'). 



Madrejpora Kenti. 



Corallum horizontal or corymbose, with important branchlets 

 on the under surface as in M. bifaria^ but tliey are here not 

 quite so stout as those on the upper aspect and the corallites 

 are less prominent. Upper series of branchlets 3*5 to 6 

 centim. long and 7 to 10 millim. diameter. Apical coral- 

 lites 2-5 to 3 millim. diameter, cylindrical. Lateral corallites 



