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LETT’S HEPATICS OF THE BRITISH ISLANDS.* 
Marshall A. Howe. 
*H. W. Lett. A list, with descriptive notes, of^all the Hepatics hitherto found in the 
British Islands. Published by the author, Aghaderg Glebe, Loughbrickland; Co. Down. 
1902. Pp.l— VIII-1-90. Price, 7s., 6d. 
This work, which is a descriptive manual rather than a “list,” is an 
attempt to popularize the study of the Hepaticae of Great Britain and Ireland. 
The language of the work, as the author states in the preface, “ is not that 
usually found in botanical books, and which needs the assistance of a dic- 
tionary of Botanical terms or a vocabulary, but plain simple English.” The 
author’s purpose to employ simple language is rather well carried out, 
though certain terms like “monoicous,” “ dioicous,” and a few others that 
occur in nearly every description are probably as susceptible to impeach- 
ment in the. role of “plain simple English” as would be several other telling 
technical terms that are studiously avoided. The use of the metric system 
for measurements, which deserves speedily to become “ plain English,” even 
though not generally considered so at present, is to be commended. 
In general plan and typography, the book suggests Dixon and Jame- 
son’s popular Handbook of British Mosses, and like that, it is a work that 
will prove of service to. the American as well as to the British beginner in 
the study of bryophytes. But unhappily for the less experienced student, 
for whom the wrnrk is primarily intended, there are frequent errors or inac- 
curacies of statement which may mislead rather than help. Some of those 
have been listed by Mr. Symers M. Macvicar in a review, published in the 
Journal of Botany for December, 1902. Among those not noted by Mr. 
Macvicar may be mentioned the following remark under Anthoceros punc- 
tatus: “When without fruit they might be taken for young states of Pellia r 
but may be distinguished with aid of a lens, by the absence of true stomata- 
pores in their surface and by the large cells.” As a matter of fact, the exist- 
ence of “true stomata-pores ” or pores of any other kind \n Be Ilia has, so 
far as we know, never before been hinted at by any one, while in the epi- 
dermis of the Anthocerotaceae there are actually inconspicuous clefts 
(especially on. the ventral surface) which authors have described as “stom- 
ata” or “mucilage-slits.” A very important and easily applied test which 
always serves to distinguish a sterile Anthoceros from a Pellia or any other ' 
hepatic in the narrower sense, is of course the presence of a single large 
chlorophyll body in each epidermal cell, while in Pellia each surface cell 
contains several or many very much smaller chlorophyll-bodies. A further 
remark of Canon Lett’s, under Anthoceros . Stableri, is that “The species of 
Anthoceros, if dried, are almost impossible to distinguish from each other.” 
We cannot say how it may be with A. Stableri , but we have found in prac- 
tice that Anthoceros punctatus and A. laevis, the other two species of his 
list, are best distinguished by decided differences in the. nature of the sur- 
face-markings of the spores and by their color, characters that can be 
determined as well from dried material as from the living. 
The arrangement of the genera in some parts of the book evidently fol- 
