RELATION BETWEE?f GONIDIA AND HTPHJ: IN LICHENS 181 



parasite, but in consequence o£ the changed conditions of life of the 

 parasite the gonidia cannot in any way be compensated by this 

 service on the part of the fungus. Such a correspondence in the 

 physiological relations of fungus and alga as the reciprocal supply of 

 each other's deficiencies in the numerous necessaries of the vital 

 activities of the component parts, as is implied by the mutualistic 

 theory, cannot be imagined. 



In conclusion, we should note that the fact of the more or less 

 certain absence of the cell-wall of the haustoria inside the living 

 gonidia, while the protoplasm of the fungus carries on its physio- 

 logical function in immediate contact with the gonidial protoplasm, 

 recalls the teaching of the famous mycologist Eriksson. Perhaps the 

 gonidia on becoming separated from the mother cells already carry in 

 their protoplasm some beginning of the fungus, in this way nursing 

 its own parasite. May not Eriksson perhaps be right in his supposi- 

 tion ? It is unfortunate that this important theoretical and practical 

 question has yet to be solved, and has not received its fair critical 

 investigation in spite of the fact that its importance makes it deserve 

 the most searching examination. 



EAST WILTSHIRE MOSSES AND HEPATICS. 



By C. p. Hukst. 



M08SES. 



The following mosses were gathered in the winter and spring 

 1917-191S around Great Bedwyn, which lies about seven miles to 

 the south-east of Marlborough in East Wiltshire, and is near Saver- 

 nake Forest and not very far from the county boundary between 

 Wiltshire and Berkshire. This border village is situated on the soft 

 white Marsupites testudinnrius zone of the Upper Chalk near the 

 apex of the London Basin, but the calcareous /aeries of the moss flora 

 is very much masked by the occurrence of Eocene outliers and Pleisto- 

 cene layers of sand, gravel, and clay in the neighbourhood. Tlie 

 Kennet and Avon Canal passing through Great Bedwyn divides 

 Wiltshire into the two vice-counties North Wilts (v.c. 7) and South 

 Wilts (v.c. 8). All the localities and a number of the mosses are 

 additional to those in my papers " East Wiltshire Mosses " and 

 "County Lists of Mosses" in this Journal for 1916, pp. 17-24, 

 262-274-. The arrangement and nomenclature of the Census Cata- 

 logue of British Mosses (1907) have been followed, and I am much 

 indebted for kind assistance and notes to Messrs. H. N. Dixon, 

 H. H. Knight, and W. Ingham. The list contains sixteen new vice- 

 comital records for Wiltshire, the greater number of which were made 

 close to Great Bedwyn, and forcibly illustrates the maxim that the 

 more a district is examined the more it produces. 7 = North Wilts ; 

 8 = South Wilts; c.fr. = with fruit; * = new vice-comital record. 



Poli/trichum nanum^(ick. 7*. C.fr., rather plentiful in an old 

 excavation for gravel near London liide, Savernake Forest ; abundant 



