172 . BOTANICAL GAZETTE. 
Number of Species of each of the Principal Types of Vegetation that hawe been 
present time, as nearly as it is possible to ascertain, together with the 
— 
CRYPTOGAMS 
VASCULAR. 
GEOLOGICAL FORMATIONS. tae: 
Rhizo- |Equise- |Lycopo- |Ligu- 
Ferns. | carpee.| tine.| dine.) late. 
| 
No. |p. ¢.| No. |p. ¢.| No.|p. ¢.| No.|p. ¢.| No.ip. ¢. No. |p. ¢. 
- Present time. | i 2.05) 100) 0.07) 30 
(Quaternary. wsenceevese eores| 27} 33.8} 4) 4.9) .cssslecseeee 2 
eS 37\ 55.2 
3 ocene, aoa 3 3.1 
§ | Mioce 138} 5.5) 871 2.9 0.2) 18 
£/3 Oligocene Ad] Set BG eee a AR Ss 
3/3 \Green Rive 5). 22 8) 86 0.9} 3 
~|\Eocene TAL 10.0]. Sar Me Muses oryens 1 
Paleocene 3} 2.5 i 5.9 
| {Laramie. a 13; 3.9) 23) 6.9 1) OB 4 
(Bionian RMN See Biagay 22) igo” OOF | Bay apna 1 
=/Turonian 1) 20.0 20.0 
¥|Cenomanian ...... 8 3.8) 38) 15.5) 1 O04 1 
3 Dakota 1) 0.5 3.3)... 
2 |Gault...... 10) 27.8 
=o |Urgonian | 50} 46.3) 1) 0.9} 8 
| |Necomian | 10! 25.6, 12| 30.8 
Z {Wealden 7| 5.8| 44] 36.4 soe] seenloene 
Sig Coral 19) 20.2) Ter IB Ab sn. eer” ated Temes 
= Oolite, 39} 9.8} 188] 81.7} 1] ©.3] 14] 3.8] 8) 0.7) nsseejee * 
s Lias 15) 9.7) 4 S26. MY: SQ i cdcs fide annen|eseeere 
>) Rheti 8 6.3): GO) 64-8)... bescoen 5] © BD csces]s serene seceee] sees 
3 Keuper......... BET BOB ccscscls cccsen 8} '7.Bhisssea}eeresno]sooneel® ween 
WR USCMOME occ s eoccis ccc csesck 2! 33.3) 1) 16.7 \ sense] ronsea|cooter® 
Bunter Sandstein cj iki Pane Tj 4 5j.yesee|e coerce errr vensene 
MONIT ca agi csees cise aeisececs 6| 1.8] 186] 55.4)... 26} 7.7} HD Teaseanh rere 
S Carboniferous .....cscocssesceress sees 27, 1.2 OOH AZ Ae 143] 9.7} 368) 24- ~ 
: b-ea __ ms 5! 3.7\ 641 47.4) 1) 0.8] 20) 14.8) 25) 18.5)....0-j-- 
3 GHEBN. «ci cciuleiredosnc tae soa 83/ 17.6] 79] 42.0' 3) 21.6] 16) 8.5] 28} 14.9). 
© |Upper Silurian..........csccceee vel BL OLS) A GM eae 1] 7.7] 1) TeTrovnenjenrerm 
=| Lower Silurian ............ eccibavnce 40) 90.9) TP 28h ad ocx tt BSP. 2 ne 
brian 21100.0 | ore 
inee and the Lycopodinee in the Carboniferous, the Cycadacet : 
in the Lias or Oolite, the Conifer in the Wealden or Neocom-— 
ian, the Monocotyledons in the Eocene, the monochlamydeous — 
Dicotyledons in the Cenomanian, the polypetalous Dicotyledons — 
in the Miocene, and the gamopetalous Dicotyledons in the pres 
ent living flora of the globe. : has 
Il. Probable true period of origin and of maximum a 
lute development of each type. 
