136 MADEEPOEAEIA. 



The under surface of the larger branches bears immersed or extremely short corallites only. 

 The axial corallites are provided with 12 septa, all well developed, but a short distance below 

 the margin they commence to taper away, thus forming a funnel-shaped cup. There are also 

 two cycles of septa in the radial corallites ; the directives are extremely well developed, and 

 often meet in the middle line, the other primaries are narrow, and the second cycle is still less 

 prominent. Coral lum rather porous ; surface spongy-reticulate ; wall fenestrated when thin, 

 more or less distinctly striate in other cases. 



Verrill regards M, secunda as a variety of this species, but, so far as one can gather from 

 the original descriptions, they appear quite distinct. The specimens which I have referred to 

 M. secunda are certainly distinct. Two specimens in the collection from Singapore, named 

 and received through the Museum of Comparative Zoology, do not appear to me to belong to 

 this species, and have been referred to M. brueggemanni var. uncinata. 



Singapore. 



a. Singapore. Dr. Briiggemann [P.]. 77. 12. 12. 1. 



b. ? Purchased. 56. 2. 18. 29. 



c. ? C. Johnston, Esq. [P.]. 44. 4. 10. 1. 



d. ? Purchased. 47. 1. 19. 4. 



e. ? ? 93.4.7.108. 



/ ? Purchased. 57. 1. 19. 5. 



g. ? ? 30. 12. 15. 1. 



h. Java. Purchased. 59. 12. 12. 7. 



137. Madrepora canalis. 



Madrepora canalis, Quelch, ' Challenger' Reef Corals, p. 150, pi. ix. fig. 2. 



Corallum arborescent, consisting of stout branches 2 to 2*5 cm. thick, giving rise at 

 intervals to clusters of 3 or 4 branchlets at the same level ; the older ones 6 or 7 cm. long 

 and nearly 2 cm. thick near the base, gradually tapering ; apical branchlets about 1*5 cm. 

 long and 7 mm. thick. Axial corallites 3'5 mm. diameter, not exsert ; wall thick and very 

 porous ; septa in two cycles, both well developed. Radial corallites spreading almost at right 

 angles, crowded, chiefly dimidiate, with a very thick wall, thicker (1 mm.) at the margin than 

 below, 2 to 3 mm. long and 3 mm. diameter across the spout-shaped and thickened apex. A 

 few smaller, chiefly labellate, corallites are scattered between the others, but scarcely destroy 

 the general symmetry. In the radial corallites the septa are in two cycles, but the directives 

 are here distinctly broader than the others. Corallum porous ; surface reticulate and strongly 

 echinulate; waU very porous, striato-reticulate and echinulate. 



This species resembles M. nobilis closely in mode of branching and in the thickened 

 porous wall of the radial corallites. The axial corallites are, however, not exsert, and the 

 radial ones are decidedly broader at the apex than below, erect, and subequal. 



Philippine Islands. 



a. Samboaugan. H.M.S. ' Challenger.' 86. 12. 9. 268. (Type.) 



