FKTEDHICU EHKIIAHT AND HIS EXSICCA'IM- J327 



the interest which I found in its siihject — an interest ^vhich I liope 

 my readers will share, at any rate to some extent. I am much in- 

 debted to Mr. Gepp for the help that he has given me by translating 

 the German notices of Ehrhart and in assisting me to sunnnai-ise 

 their contents. Tlie connexion of Ehrhart with the Sf/pj^/emrnhnn 

 Plautarum will form the subject of another communication which I 

 hope w^ill prove of equal interest ; it will certainly be less lengthy. 



PosTSCEiPT. While the present paper was passing through the 

 l)resS; the following important passage from a letter of Ehrhart 

 (Dec. 8, 1794) to Usteri {Annalen, ix. 105; 1794) has come to 

 light ; it gives further details about the Exsiccatai and the proposed 

 addition to the Beitrdye : — 



" 1 am now beginning to publish the continuations of my exsiccata?. 

 This winter you receive Decades 15 and IG of the Arhores, 15 and 

 1*) of the Herbce, 13 and 14 of the Calamarice, 25-82 of the Flautce 

 (Ji'tjplui/iimcB, and 9-lG of the Bluntce Selectee liortuU 'pro])rii. 

 Tlie still- wanting 14 of tlie promised GO Decades of the FlantcB 

 OJficiiiales 1 can however not deliver before Michaelmas, since 

 1 still lack some of the plants belonging thereto. At Easter also the 

 8th Band of my Beitriige comes out, and perhaps also soon the 

 9th Band." 



SPITZBERGEN LIVEKWORTS *. 

 Br W. Watson, D.Sc. 



Dl'kixg the Spitzbergen Expedition of 1921, Mr. Y. S. Summer- 

 hay es collected a number of Liverworts, which were sent to me for 

 identification. They were collected during June and July at alti- 

 tudes varying from 20 ft. to 1200 ft. Their habitats were carefully 

 noted and supplied to me by the collector, and this knowledge was of 

 great service for ready determination. Twelve samples were packed in 

 the usual way in paper wrappers, and 24 were i^laced in tubes with a 

 solution of formalin ; the latter method is unsuitable for Liverworts 

 as it gives them a uniform dark tint, and causes them to break up 

 during subsequent handling and dissection. Few samples had peri- 

 anths, and in the determination from vegetative characters only, the 

 colour is a great help in readily identifying the species. Another 

 disadvantage of the formalin preservative is that it renders the plant 

 useless for preserving in the usual way. Gemmre were very scarce, 

 being found in only a few plants. 



Material was sup})lied from the following localities and habitats : — 

 Bear Island : Dry tundra, below 100 ft. ; rock-crevices or among 

 boulders, 100 ft. or about 1200 ft. ; wet region ('Irainage channel), 

 50-100 ft. ; Hermansen Island : bogs, below 100 ft. ; Ad cent Bay : 

 boggy area and damp moss tundra, 30-100 ft. ; Ga]oe Boheman : I'ock- 

 crevices, 50 ft. ; bogs below 50 ft. ; Prince Charlea Foreland : damp 

 slopes, etc., 30-700 ft. ; Klaas Billen Bay : edge of pond, 20 ft. ; 

 Gi2)s Valley : moss bog by river below 50 ft. 



In the determination of a few critical plants I have had the kind 



* Eosiilts of the Oxford University Expedition to Spitzbergen, No. 19. 



