88 califoknia academy of sciences. 



Differential Characters of the Three Californian Species of Caryophyllia. 



Septa in four cycles ( form coruute; twelve more prommeut costas ) C. pedroensis 



I form short, inversely subcouical, cost;© i 



^ eqnal near the calice, alternating iu size [ C. arnoldi 



( near base ) 



Septa in four com- 1 j 



plete ej'cles, many ) form subflabellate, costne excepting near the I p ,. , 



members of the tifth 1 calicular margin indistinct ( ' ^" ijormca 



present ( ) 



As the descriptions and the above table show, for the differentiation of the spe- 

 cies, especial stress is laid upon the number of the septa, the form, and the costal charac- 

 ters. Although each of the three species is based on a single specimen, the author does 

 not believe it possible for intergradation to occur within the horizons from which 

 they were collected. C. pedroensia and C. arnoldi appear to belong in the same 

 group (section) of the genus; but C. califomica presents great and striking differ- 

 ences from each of the preceding. 



Genus Paracyathus Milne-Edwards & Haime. 



Verrill has described three species of Paracyathus from the west coast of 

 North America, viz.: Paracyathus caltha,^ Paracyathus stearnsij^ and Paracyathus 

 humilis.^ The first two species mentioned are from Monterey, California; the last 

 mentioned is from the Pearl Islands. 



Expressed in tabular form the differences between these three species are: — 



f CostiTB distinct only at edge of calice, be- 1 

 „ ,, K • < I low represented by rows of granules; axes of > P. callha 



Uorallum 5 in or ^^,j^^ ^^ in. /.32 in 



more in height; nve J ' ' 



complete cycles of j glabrous, subequal costaa, distinct to base, ^ 



^ P^ I near base every fourth or sixth costa more ; P. slearnsi 



{ prominent; axes of calice, .72 in. /.50 iu . . . . ) 



i^ora nm ori y ._ n. i Q^g^.g feeble, except near calicular margin. / „ i -i- 



in height; four com- diameter of circular calice, .22 in ^- ^«»"'" 



plete cycles of septa. ( ) 



According to the diagnostic characters given by Verrill, these three species 

 are very distinct. 



4. Paracyathus pedroensis Vaughan, sp. nov. 



Plate III, Figs. 1 and la. 



Corallum subturbinate in shape, base damaged, apparently not especially expanded; trans- 

 verse outline of calice elliptical, slightly deformed. 



Costse not prominent, but distinct from the calicular margin to the base, subequal, some- 

 times every third or every fifth may be slightly more prominent than those intervening, the edges 

 usually flattish, sometimes slightly crested. Bottoms of the intercostal furrows usually flattish; 

 granulations crowded on the costse, and present in the intercostal furrows also. 



1 Proc. Boat. Soc. Nat. Hist., Vol. XII, 1869, p. 394; Trans. Conn. Acad. 8ci., Vol. I, 1870, p. 637, Pi. IX, figs. 9, 9a. 



" Proc. Bost. Soc. Nat. Hist.. Vol. XII, 1869, p. 393; Trans. Conn. Acad. Sci., Vol. I, 1870, p. 537. 



'Trans. Conn. Acad. Sci., Vol. I. 1870, p. 638. 



* These decimals of an inch can be computed into millimeiers by reckoning ,1 inch = 2.6_mm. 



