of the British Species and Genera of Graptolites. 355 
been found, viz. Climacograpsus teretiusculus, a highly cha- 
racteristic Lower-Silurian fossil. 
In the Wenlock rocks there is but one peculiar species, 
namely Graptolites Flemingii; G. priodon and G. colonus 
being common but not confined to the group. The sole pecu- 
liar species, G. Flemingii, is only known to occur in one loca- 
lity (Balmae in Kireudbright), in beds supposed to be of the 
age of the Wenlock Shale. ettolites Geinitzianus has been 
looked upon as a characteristic Wenlock form; but it occurs 
abundantly, with Lower-Silurian species, in the Coniston 
Flags, and it appears to have lived on into the Ludlow 
period. 
In the Lower Ludlow rocks the beautiful Prilograpsus 
anglicus has hitherto been exclusively found, whilst in both 
the Lower and Upper Ludlows G. priodon and G’. colonus are 
of common occurrence. 
Subjoined are tables showing the distribution in time of the 
genera and species of Graptolitidee which have been discovered 
in Britain. 
Table showing the Vertical Distribution of the British Genera 
of the Family of the Graptolitide. 
wn 4/0/10 O!1o 
OD} on OD ra | el > . . 
Sl/OOrals ols = 
S\zelshs| lee] (8/6 
MQiaa|dl_ a\qa oo 
oJ 4/,S1S] (Sis! s/s 
Genera. Sle eltoisldig esha ha 
is BS leals S His 5 
S leg B/S)olS/o/S)5 | & 
BIS O/B 28 /E) 2) 8/F/ a 
Bld |} CO), F138 | |S onnen 
ABeCHpidiWbe Ib 
WMietyoneman. 6. eielel sa s+ ancots x * x 
Dichograpeus -. 20. 6c sete ede - % 
Detracrapsus: *. vs .)s ccd e « * 
Phyllograpsus:.. 0... sss |>. * 
Dendrograpsus 1.66 0:....4e. aw lale |x 
Climacograpsus ..........].. x |xlel «|x 
Diplograpsus ........0%%%[0- x laelelx 
Didymograpsus ..... ...% 0. x lal al x 
Pleurograpsus . si. .!o.0::.r4 + Blane ge 
Graptolites Se eR ee Oa, E P ea ae oe ee 
TRASTITGCS Bays pee eth ord enema tins ‘ x | 
Helicoprapsus's : io). icasni|o- #* | 
Cyrtograpsus ......+...44/.- Aes 
IRGhlolitesee nem ria rererane lee le] & le] xe 
DicranOgrapsus. i. vice. screnade « oo aed ge | 2 
Callograpsus, ....0.6se0e|e. Boel oo el 
Ptilograpsus: 220... cis..rtanewhe « wv? fered clerofelo|aro| oro] ae 
| | 
