59i 
Life-history of Tetraclinis articulata . 
thirds of the way down, which was unfortunately cut through when the 
prothallus was fixed, so that the number of archegonia cannot be counted ; 
two, at least, can be clearly seen, and in the sketch the group has been 
hypothetically restored. The third preparation (Text-fig. 4) resembles the 
Text-fig. 2. — Median longi- Text-figs. 3 and 4. — Median longitudinal sections of two 
tudinal section of apical part of a prothalli of Tetraclinis, containing lateral groups of arche- 
prothallus of Tetraclinis, contain- gonia. Both X 35. Fig. 3, Sept. 23. Fig. 4, Oct. 3. 
ing both apical and lateral groups 
of archegonia. x 35. Sept. 2. 
first in having one apical and one lateral group of archegonia, but in this 
case the lateral group lies about half-way down the prothallus. 
It is noteworthy that each prothallus which shows lateral archegonia is 
very healthy and well developed. In each case pollen-tubes are developing 
quite normally through the nucellus, and the archegonia themselves appear 
normal in other respects, and healthy. There is not the slightest indication 
