350 Mr. J. Miers on the Calyceraceae. 



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 elevat ion in other parts ; 

 and geologists have yet a great deal to do and learn before they 

 can elucidate this difficult problem. 

 Oct. 10, 1860. 



XLV. — On the Calyceraceae. 

 By John Miers, F.R.S., F.L.S. &c. 



[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, in each axil of the dicho- 

 tomously branching stems; the involucre is thin, membrana- 

 ceous, cup-shaped, divided half-way down into a 54oothed 

 border, its receptacle being reduced to a small point scarcely 

 larger than the summit of the peduncle, and in some instances 

 quite void of palese. The achsenia 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 avo/jbos, inaqualis; fcapwbs, fructus. This habit prevails 

 in the three first-mentioned species; but in the fourth the 

 stems disappear, the plant becoming completely depressed and 

 csespitose ; 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 

 cit'spitose proportions. Each capitulum represents a depressed 



