GENERA OF TAXACEXH AND CONIFER. 15 
axis of the cone is not prolonged beyond the scales as it is in 
Callitris. Desfontaines, ‘Flora Atlantica,’ t. 252, figures the 
male flowers as well as the cones. The fossil species from the 
Tertiary formations named Callitris Brongniarti (Renault, ‘ Cours 
de Botanique Fossile,’ Coniféres, tab. 15. fig. 9) appears to belong 
to this genus rather than to Callitris proper. 
For a summary account of the Gum Sandrac tree of Marocco 
see Hooker and Ball, ‘Marocco and the Great Atlas,’ Appen- 
dix D; and Luerssen, ‘ Medicinisch-Pharmaceutische Botanik,’ 
Band ii. (1882), p. 98, fig. 37. 
CALLITRIS. 
A genus established by Ventenat * in 1808 and founded upon 
a single evergreen Australian tree to which no specific name was 
attached, but which was probably that now known as C. rhom- 
boidea. It is synonymous with Frenela of Mirbel, who, in 1826, 
substituted the name Frenela on account of the similarity of 
sound between Calilitris and the Myrtaceous genus Calythriz. 
The genus has been understood in various ways by different 
authors. Richard, Endlicher, Parlatore, Eichler, Bentham, and 
others refer the North-African Thuya articulata to this genus, 
but, for reasons cited under the preceding genus, it seems to me 
to be preferable to consider the Barbary plant as the representa- 
tive of a distinct genus (see Tetraclinis). The South-African 
Widdringtonia (alias Pachylepis of Brongniart) is also often com- 
prised under this genus, but this also I propose to keep separate. 
As thus circumscribed Callitris comprises only Australian and 
New-Caledonian species, but includes the genus Leichartia of 
Shepherd and the Octoclinis of F. von Mueller. 
Callitris has its vegetative organs similar to those of its allies, 
but differs from them in the presence of 6-8 unequal verti- 
cillate scales to the cones and of numerous seeds to each scale. 
Unlike what happens in <Actinostrobus, there is an abrupt 
transition between the leaves and the cone-scales, whilst these 
latter usually show externally traces of their essentially composite 
nature. The erect seeds, as may be seen from the cicatrices they 
leave when they fall from the scale, are arranged in a somewhat 
decussate manner: thus we see, first, one scar at the base in the 
* Dec. Gen. Nov. 1808, n, 10. 
