510 ZOOPHYTES. 



continued, they go on to accumulate, till it is lost by a complete 

 coalescence of all the depositions and a filling of the cell internally, 

 thus rendering the coral quite solid within. This is the case with 

 the Seriatoporae, and also with some of the smaller Pocilloporse, 

 although the larger species of this last genus contain the septa as 

 distinct and regular as the fossil Favosites. 



The cell is usually shallow, and is bordered around by six to 

 twelve lamellae, generally entire and often quite narrow, or even 

 obsolete : their size varies from a mere point to a line and a half. 

 There are no prominent calicles, and only a few branching species 

 have the upper side of the cell a little projecting. 



The FavositidfB grow in glomerate or massive forms, and in ramose 

 shapes. The latter enlarge by the budding of a parent-cluster, and 

 branching consequently takes place by furcation, producing crowded 

 cespitose clumps, which are usually hemispherical in outline. In 

 some species, the separate polyps are imperfectly coalescent, or are 

 united laterally only by their non-secreting exterior integuments, and 

 their secretions form separable columns or tubes. 



The corals of this family, in the present seas, are confined to the 

 coral-reef latitudes, and the known species are from the Pacific and 

 Indian Oceans, and seas adjoining. 



The Favositidse may be divided into three subfamilies: 



I. ALVEOPORIN^;. Cells contiguous, slenderly echinulate within ; 

 parietes cribrate. 



II. FAVOSITIN^:. Cells contiguous, at the summits at least; rays 

 entire or obsolete. 



III. HELIOPORIN.E. Cells in no part contiguous, circular. 



SUBFAMILY I. ALVEOPORIN^. 



FavositidcB spongiose coralligence ; cellis angulatis, contiguis, intus tenui- 

 ter echinulatis. 



Favositidse, forming spongy calcareous secretions ; cells angular, con- 

 tiguous, internally slenderly echinulate. 



