Mao Scientific Intelligence. 
tion of the animal when living. Under such circumstances, it is not suf-— 
prising that various opinions have been Rg ae depending in a great 
measure upon the state of get of ossils examined. The e | 
diminution in the dimensions, or perhaps we cae rather say in the de- 
velopment, of the cellules or ssifisions of the axis towards the base, has 
given rise to the opinions, earn by Barrande, that the extension of 
the axis by growth was in that -direction, moe a t these smaller cells 
were really in a state of increase and developme “hs opposition to this 
argument, we could before have advanced the Sion furnished by & 
bicornis, G. ramosus, G. sextans, G. furcatus, G. tenuis, and others, which 
show that the stipes could not have increased in that direction. It is 
true that none of the species figured by Barrande indicate insuperable 
Gants to this view; though in the figures of G. Serra (Brong.) by 
of species as hee been made by Pasaide aera and 1 Geintz, so fer ra- 
mose forms have been discovered ; and none so far as the writer is aware, 
approaching i in the perfection of this character to the American species. 
aintaining as we do Se as view of the subject, which is borne 
out by well-preserved specimens of several species, we cannot admit the 
proposed separation of the Graptolites into the genera Monograpsus, Di- 
plograpsus, and Cladograpsus, for the reason that one and the same spe- 
cies, as shown in single individuals, may be monoprionidean or diprio- 
a — or both; and we shall see still farther objections to this division, 
__ a8 we progress, in the utter impossibility of enon a these charac- 
“ fatistics under certain circumstances. e do not yet perceive sufficient 
ason to separate the branching forms from “ee supposed to be not 
Granched, for it is not always possible to decide which have or have not 
been ramose, among the fragments found. Moreover, there are so various 
modes of branching, that such forms as G. ramosus present but little 
analogy with such as G. Sige ial 
e genus ce he es of Barrande has not yet been recogniz 
among American Graptolitidee. These rnsal are by Geinitz united to 
his genus Cladograpsus, the propriety of which we are unable to decide. 
“The genus a (Retzalites of Barrande, 1850, Graptophyllia 
=e Hall, 1849) occurs among American forms of the Graptolitidec, ina 
Single species in a Clinton group of New York. <A form analogous, 
