A STUDY OF TARGIONIA HYPOPHYLLA 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 156 
HERMANN DEUTSCH 
(WITH THIRTEEN FIGURES) 
Considerable work has already been done on the morphology 
of Targionia hypophylia, LerrceB (1) and CAMPBELL (2) being 
foremost among the investigators. Recently CAvERS (3) also 
published a paper on the same species; but with all this there still 
remains some little ground which has not been covered at all, as 
well as some which has been covered but superficially. These 
points it is the aim of this paper to try to clear up. 
The material for this study was collected in 1908 by Drs. BARNES 
and LAnp along the steep slopes of the canyon of the Rio Santiago 
in western Mexico, and also on the eastern slope of Mt. Orizaba. 
In both regions it was found only at an altitude of 1500 meters. 
Gametophyte body 
The thallus in this group is about as complex as in any of 
- the Marchantiales. This statement is not based on any one of the 
several characters that usually distinguish a thallus as simple or 
complex, but on an average of the total amount of differentiation 
and complexity present. 
In the first place, the thallus is formed by the segmentation of a 
single, cuneate apical cell (figs. 1 and 2), cutting-off segments on 
four faces. CAVERS (3) reports a row of initials at the apex. In 
none of the preparations studied in this particular instance, however, 
could this report be verified. On the contrary, they seemed to 
show very distinctly a single apical cell, distinguished from its sur- 
rounding segments both as to its size, and also as to the size, plane, 
and position of its nucleus. Relative to the apical cells found in 
the other genera of the Marchantiales, the apical cell of Targionia 
is rather small. 
The development of the air chamber is one feature which, as yet, 
has not been described. This proceeds along the lines reported by 
Botanical Gazette, vol. 53] 492 
