344 J. D. Dana on Zoophytes. 
vous system, is entitled to little consideration as a means of dis- 
tinction in the classification of these animals:—it is no more 
important here than in botany, where a plant consisting of a sin- 
gle individual bud, may be placed along side of one which con- 
sists of several. It may sometimes however be used to distin- 
guish genera: yet in the genus Fungia, there are a few species 
that increase until they consist of two or three individuals ; and 
there is thence a passage to the Herpetolithi, Eschsch. ( Hal- 
4 Ehr.) and Polyphyllie, Q. and G. The simple and 
ompound oo eat me are other examples of the difficulty of 
this separatio 
2. But the vieenlah of budding and growth are of higher char- 
acter; especially ac distinction of superior and inferior gem- 
mation, in the former the buds being terminal or at summit, 
and in the latter arr or basal. It is of little importance 
whether the summit-widening, which accompanies superior gem- 
mation, takes place in the disks, or just exterior to the disks. In 
eit e visceral lamellze are prolonged at top beneath the 
upper surface, ry the process of growth, and hence such species 
have the upper surface of the corallum lamello-striate. 
n superior gemmation, when the disks widen and bud, they 
sometimes subdivide as each new mouth opens, and sometimes 
not till several mouths have opened. This difference (distin- 
omer the genera Astrea and Meandrina) is of small import- 
ance. ‘There are Astreee in which the disks become 2 or 3-com- 
pound before they subdivide ; and thus the two genera graduate 
into one another. There are simple and meandrine Muss@, 
Oken, ( Meters hs Bi.) between which no line of separation 
can be and they have been always retained in the same 
genus. The ‘Monticularie, i in the same manner, are related to 
the ne sce as 
und species. The coralla of compound species are 
characterized by the continuation of the lamelle of the stars from 
centre to centre, without interruption along a medial line ; and 
they have no cells except it arise from a prominence of the in- 
tervals between the polyp-mouths. They thus differ from the 
Astree ; for the cells in the Astre@ correspond to the visceral 
cavities of the polyps. 
Vee ey 
*See on this subject Report on Zoophytes, pp. 76, 77, and this volume, p- 19, 
