384 West. — A Contribution to the Study of the Morattiaceae . 
not increased in complexity beyond this stage, hence it would appear that 
in the genus Kaidfussia the arrangement of the vascular strands in the 
adult rhizome is simpler than in Danaea. 
Vascidar Anatomy of the Petiole . The arrangement of the vascular 
strands in the petiole of Kaidfussia has already been dealt with at some 
length by Bertrand and Cornaille (2) and by Gwynne-Vaughan ( 30 ) ; 
according to the last-named botanist (1. c., p. 263), several (1-5) internal 
strands leave the abaxial strands of the arc, pass across the central ground- 
tissue, and unite with the adaxial terminal strands of the horseshoe curve ; 
hence they are not continued up as separate strands beyond the region of 
the pulvinus. The two terminal strands sink in towards the centre of the 
petiole and eventually fuse together across the median plane to form 
a single large strand ; this is the arrangement of the vascular strands 
as seen in a transverse section taken at some distance below the point 
where the petiole branches (Text-fig. 16, i ; and cf. Bertrand and Cornaille, 
1 . c , Fig. 86, p. 169). But in the region immediately below the point where 
the petiole branches, the large central bundle divides into six strands (Text- 
fig. 1 6, iv) ; of these six strands, two pass into each of the three main 
branches accompanied by three strands from the peripheral ring of bundles 
(Text-fig. 16, v-vii) ; these together form an anastomosing ring of strands in 
each of the three primary branches of the petiole. Two or more strands 
leave the ring of bundles to supply the secondary branches of the petiole 
(Text-fig. 16, viii-x). 
3. Archangiopteris} 
Our knowledge of the general morphology of this monotypic genus is 
still far from complete, and it is impossible to decide from the information 
available whether the stem of the adidt plant has a radial or a dorsiventral 
organization. Gwynne-Vaughan ( 30 ), who investigated the anatomy of 
the petiole and of a small fragment of the stock, states that the arrangement 
both of the leaves and of the vascular strands in the stem indicates a radial 
symmetry. An examination of herbarium specimens by the present writer 
lends support to this view. 
Archangiopteris Henryi has simply pinnate leaves and closely resembles 
the larger species of Danaea. 
According to Gwynne-Vaughan ( 30 , p. 261), the vascular system of 
the stem consists of a single dictyostelic ring of two to four small strands, 
which anastomose with each other in a somewhat irregular manner ; in 
addition there is usually a small internal ( = commissural) strand which runs 
free in the central ground- tissue through the greater part of its course, and 
from time to time approaches the dictyostelic ring, fusing with those 
1 For information regarding the morphology of the frond of Archangiopteris Henryi , the 
reader is referred to Pteridographische Notizen, published by H. Christ and K. Giesenhagen in 
l lora, Bd. lxxxvi, 1899. 
