350 Mr. J. Miers on the Calyceracee. 
in England. The only satisfactory mode of accounting for this 
partial distribution of land animals would seem to be the great 
and continual alterations which have, from time to time since 
the commencement of the Tertiary epoch, successively taken 
place in the relative position and quantity of land and water, 
caused by subsidence in some, and elevation in other parts ; 
and geologists have yet a great deal to do and learn before they 
ean elucidate this difficult problem. 
* Oct. 10, 1860. 
XLV.—On the Calyceracez. 
By Joun Miers, F.R.S., F.L.S. &e. 
[Continued from p. 288.] 
4, ANOMOCARPUS. 
I have already alluded to this genus, which differs from all 
others of this order in many esssential characters. The inflo- 
rescence generally consists of a single head of a few florets 
standing upon a very short peduncle, m each axil of the dicho- 
tomously branching stems; the involucre is thin, membrana- 
ceous, cup-shaped, divided half-way down mto a 5-toothed 
border, its receptacle being reduced to a small point scarcely 
larger than the summit of the peduncle, and in some imstances 
quite void of palee. The achznia are remarkably dissimilar in 
form; in some the calycine lobes retain their original shape, or 
become almost obsolete, while in others they become greatly 
elongated into subulate, rigid, concave, straight, patent, and 
almost spinose expansions: hence the generic name, derived 
from dvomos, inequalis; xaptros, fructus. This habit prevails 
in the three first-mentioned species; but in the fourth the 
stems disappear, the plant becoming completely depressed and 
ceespitose ; the cauline leaves thus come to be entirely radical 
and radiating, each bearing upon its petiole an almost sessile 
capitulum, the whole plant forming a somewhat hemispherical 
head, as in the genus Nastanthus. This species is the Calycera 
pulvinata of Remy, from whose description it formerly appeared 
to me to constitute a new genus, which I suggested under the 
name of Discophytum (Lindl. Veg. Kingd. 703), agreeing with 
Nastanthus in its peculiar habit, and approaching Anomocarpus in 
other respects. Subsequently I obtained a sight of the plant, 
and its examination convinced me that it agrees perfectly with 
the latter genus in its floral and carpological structure, and is 
dissimilar in no respect except in its habit, which is entirely due 
to the complete depression of its axis, by which it is reduced to 
ceespitose proportions. Each capitulum represents a depressed 
