424 G. HERBERT FOWLER. 



support of the body wall (fig. 11, a i), but here and there they 

 fail to touch it (ibid., a 2 ), thus allowing of a cross commu- 

 nication between the longitudinal canals. The number of 

 longitudinal canals is thus double that of the ectocoelic and 

 entoccelic spaces, since the body wall is in contact both with 

 true costae and with pseudocostae (i. e. those which replace the 

 peripheral lamellae). In the single perfect specimen of the 

 corallum in the British Museum, the pseudocostae are dis- 

 tinctly visible on the upper two thirds of the exterior of the 

 calyx, but below this are lost in the true costae. Unfortu- 

 nately my fragments did not show the relations of the soft 

 tissues in the lowest third. 



Figures and a description of the corallum may be found in 

 Moseley, " Chall." Rep. Zool., ii, p. 157, pi. vi. 



Stephanaria planipora (fig. 13). 



A specimen of a Psammocorid coral, for which I am again 

 indebted to the generosity of Professor Moseley, appears to be 

 identical with specimens of the above-named species in the 

 British Museum. It is not recorded by Quelch ("Chall." 

 Rep. Zool.), and therefore adds another to the " Challenger " 

 species of Reef-corals. For the identification of this and 

 many other corals, and for much other assistance, I desire to 

 acknowledge my great obligation to Mr. Dendy, late of the 

 British Museum. 



The boundaries of the various polyps which compose the 

 colony are so ill defined that it is impossible to decide how 

 much of the soft parts seen in a transverse section should be 

 referred to a particular individual. A glance at a figure of a 

 section cut transversely to the axes of the polyps will show 

 this (fig. 13). Each polyp possesses a stomatodaeum, to which 

 are attached a certain number of mesenteries, generally seven 

 to ten ; between these mesenteries lie entoccelic and ectocoelic 

 septa, and over each entoccelic (?) septum is placed a tentacle 

 of the simple character already described for Seriatopora, 

 Madracis, &c. (" Anat. Madr./' iii, fig. 11). The muscles, 



