dh nroTA( i r. 37 



liarities can clearly be seen, yel it must be admitted that 

 other individuals arc frequently found which Bhow them 

 in a more or less r eakened state, and approach in a greater 

 or Leas degree to sonic of the forms of P. latifolia, bo that, 

 on the whole, I am disposed to consider these Bpec 

 not permanently distinguishable from each other. 

 45. tenuissima j 7% th rv fh'm Punctaria) j h-oud Bublinear, 



thin, transparent, Grev.Alg.Brit.p.ZA. (Atlas, PL XIII. 

 Pig. 51.) 

 Punctaria undulata, -/. Ag. Dlya plantaginifolia, Lyngb. Di- 



ploetromium plantagineum, Ktz. 

 Huh. Parasitical on Zostera marina^ Chorda filum : etc., ncu* low- 

 water mark. Annual. Summer. 



- species has never been found in a state of fruit, 

 ami hence some botanists (among others my valued friend 



Griffiths) regard it as the young i^i' some other spe- 

 cies, perhaps of P. latifolia, with which it> substance more 

 nearly agrees than with that of P. plantaginea. Hut its 

 great difference in form seems to forbid such an opinion 

 being hastily adopted, particularly as young P. latifolia 

 may he found oi' much smaller size, and with a broader 

 and more ovate frond. The plant does not seem to be found 

 all round our coast. 



XXIV. A<I>EROCOCCTS. 



4G. compressus {The compressed Asperococcus) j frond com- 

 pressed, flat, linear-lanceolate, obtuse; dots of fructification 

 oblong, Qriff. Ms. Hook. />'. F. v. 2.p. 278. \ I LS, PL XI. 

 Fig. 44.) 

 HalogloB8um Ghrimthsianum, Ktz. 



11 ah. Southern Bhores of England. Parasitical on Algsa, beyond 

 Low-water mark ; usually cast on Bhore. Annual. Summer. 

 An interesting plant, curiously connecting the genus 

 ococcus ami Punctaria, having a frond nearly inter- 

 mediate in character between that of these genera, hut 

 3sing rather more of the structure of the former. It 

 appears to be of nol (infrequent occurrence in the Medi- 

 terranean, several stations being recorded; and I have 



gathered very Large specimens at the Cape ^^ Good I 



much larger than any others that I have seen. In the 

 British seas it has as yet only been found along the south- 

 ern shores of England ami in the Channel [slands. 



J7. Tumeri frond inflated, cylindri- 



