ST. ALBANS AND ITS NEIGHBOURHOOD. 
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Biploplyllum albicans, Jungermannia crenulata, J. incisa, Nardia 
scalaris, and Fossombronia pusilla. 
Algjk.— In spite of the paucity of our information as to the 
Algal Flora there is sufficient to show that it compares favourably 
with that of other counties. 
The following list of genera and species from a pond in 
the district will sufficiently illustrate the character of the Algal 
Flora in the stiff clay:— Spirogyra catseniformis, S. Hassallii, 
S. quadrata, S. tenuissima, S. varians, Fudorina elegans, 
Pandorina morum, Clsetoplora elegans, (Edogonium sp., 
Tribonema, Opliocytium, Zygnema, Microspora, Cosmarium spp., 
Closterium lunulatum, C. Jcutzingii, C. acerosum, JJlotlrix zonata, 
Microthamnion, Mougeotia,Ankistrodesmus, Splserella, Cllamydo- 
monas,Gleocystis,Splserocystis characium, Clathrocystis, Anabsena, 
and Oscillaria, with numerous diatoms. 
In the more peaty soils such as one finds at Colney Heath 
and Brieket Wood, desmids are a prominent feature; among 
the more interesting Algae found in such habitats may be 
mentioned Closterium cornu, C. incurvum, Neplrocytium lunatum, 
Clroococcus turgidus, Bulbochsete varians, Aplanoclsete, and 
Palmodactylon varians. 
The Algal periodicity recently investigated by Fritsch & Bich 
(‘ Ann. Bot.,’ vol. xxi, July, 1907, and ‘ Proc. Bristol Hat. Soc.,’ 
vol. ii, pt. 2, 1909) is seen to advantage in the district. The 
spring phase is characterized by the abundance of such genera 
as Spirogyra, Zygnema, and Microspora, all three frequently 
forming almost pure cultures ; in the summer these give place to 
(Edogonium spp., Cladophora, and epiphytic diatoms; and the 
autumn phase is marked by the almost entire absence of all 
forms except Diatomaceae. 
Only two species of Clara have been recorded for the district, 
viz. Clara vulgaris and C. lispida K 
3. Lichenes, Fungi, and Mycetozoa. 
Lichenes. —The published records of the lichens observed in 
our district are but few, being limited to three brief lists in 
the reports of our field meetings (‘ Trans.,’ Yols. Ill and Y), one 
for St. Peter’s, containing 7 species, and the others for Brieket 
Wood, in which (excluding duplicate records) 16 are enumerated. 
Two are common to both localities, so that the total number is 21. 
So far as can be judged from this small number of records the 
most frequent species is Parmelia caperata, that being the only 
one which is common to the three lists. The rarest species are 
Calicium melanoplseum and Pertusaria globulifera, both detected 
by Mr. E. M. Holmes at our fungus foray in Brieket Wood 
in 1885. 
Fungi.— The records of the larger fungi are based almost 
entirely upon the results of fungus forays of the Herts Natural 
History Society, particulars of which are given in Yols. Ill, Y, 
YI, and IX of the Society’s ‘ Transactions.’ The localities visited 
