RETORT ON CORALS— DEEP-SEA MADREPORARIA. 



145 



MM. Milne-Edwards and Haime formed a genus Steplvanoseris for a coral investing a 

 shell with its base, found at Zanzibar, which they had previously placed in the genus 

 Heterocyathus. They removed the species S. rousseaui from the genus Heterocyathus 

 and the Turbinolidas, and placed it far apart with Fungia : because of the presence in it 

 of synapticulaa. There can, however, be no doubt from the exact resemblance in structure 

 of the septa and pali that the true affinities of the coral are with Heterocyathus, and that 

 the synapticuhe must be considered as of minor importance. The species rousseaui should 

 therefore be restored to the genus Heterocyathus, For a description of the genus 

 Stejihanoseris, and references to Mdne-Edwards' and Haimes' papers on the subject (see 

 Hist. Nat. des Coralliaires, torn. iii. p. 56). 



Deltocyathus. 



Deltocyathus italicus, Milne-Edwards and Haime. 



Deltocyathus italicus, M.-EJw. and H., Pourtales' 111. Cat. Mus., Harvard, No. 4, p. 15, pi. xi. fit's. 

 1-5, pi. v. figs. 9, 10; Ibid., No. 7, p. 35, pi. vi. fig. 11; G. Lindstrom, Actinology of the 

 Atlantic Ocean, Bd. xiv., No. 6, s. 10, pis. i. ii. figs. 13-20. 



lleltocyathus italicus ( x i). 



Deltocyathus italicus ( x 3). Stellate variety of Pourtales. 



I have little to add to the very full accounts of the many varieties of the above species 

 contained in the memoirs cited, and in Pourtales' later notes on the subject in the 

 Bull. Mus. Comp. Zool., Harvard, vol. v. No. 9, p. 200. After comparing our series of 

 specimens, which is very small in comparison with that at the disposal of Pourtales, 



(zool. chall. exp. — part, vii.— 1880.) G 19 



