4 THE MARINE ALG.'E OF ESSEX. 



by the presence of such distinctly southern forms as Grateloupia 

 fiiicina, Scinaia furcellata, Cutteria multifida, and Taonia atomaria, 

 while there is no admixture of characteristic northern species/' so far 

 as we know. 



A list of those species which may, with some degree of proba- 

 bility, be expected to occur on the Essex coast, is given at the end 

 of this paper. 



SCHIZOPHYCE^, Cohn. 



MIXOPHYCEyE, Stizenb. 



Chroococcaceae, Rab. 



(ILCEOCAPSA, Nag. 



Gloeocapsa crepidinum, Thur., " Notes Alg.," i., p. i. In 



shallow rock-pools, and also on posts at or a little above high-water 



mark. Southend, July, 1890, Mrs. T. H. Bufifham, Clacton, Jan., 



1893, E. A. B. 



APHANOCAPSA, Nag. 

 Aphanocapsa marina, Hansg , in "Foslie Contrib.," i., p. 169. 

 In shallow rock-pools, and on posts at high-water mark, usually 

 mixed with species of Ca/othn'x and other small algte. Clacton, 

 Jan., 1893, E. A. B. Rare. 



Chamsesiphonaceae, Borzi, 

 DERMOCARPA, Crouan. 

 Dermocarpa prasina, Bornet, "Notes Alg.," p. 73. On the 

 fronds of Rhodoclwrton roihii. Clacton, Jan., 1893, E. A B. Not 

 uncommon. 



HYELLA, Bornet et Flahault. 

 Hyella caespitosa. Born, et Flah., in Morot, "Journal de 

 Botan.," ii., 1888, p. 162. Growing in the substance of old shells. 

 Clacton, Jan., 1893, E, A. B. Rare. 



KORMOGONE^E, Thur. 



HOMOCYSTE.E, Born, et Thur. 



Lyngbyeae, Kiitz. 



SPIRULINA, Turp. 



Spirulina subsalsa, CErsted, " Beretning om en Excursion til 



6 Noithern species do not, except very rarely, come further south than the north of Norfolk, 

 •where: Ptiiota />lu>nosa has been reported, but on rather doubtful authority, from Cromer. Of 

 course the older records of the occurrence of " J'tilota /i/iimosa" on the coast of Devonshire, etc., 

 refers to ' ' Plumaria eifgans,' which was formerly regarded as.simply a form of Ptilota plumosd. 



