45 
of Copenhagen, and to Mr. A. D. Cotton and Miss Dickinson 
of Kew for their kindly co-operation in the identification 
of species; to Miss E. C. Herdman for the use of her 
boat and for assistance in dredging, and to the staff of 
the Marine Biological Station for unfailing assistance of 
all sorts and at all times. 
CHLOROPHYCEAE 
Sub-Order. PROTOCOCCINAE. 
Fam. CHARACIACEAE., 
Gen. Codiolum, A.Br. 
C. gregarium, A. Br. Rare. 
Fig.: Plate XV, 48, 53. 
District: Port Erm. ; 
Zone: HOW -O.S.T. 
Occurrence: Casual, Annual, Summer. 
Reproduction: July and August. 
C. Petrocelidis, Kuck. Rare. 
Fig.: Kuckuck (1894-6), Vol. I, p. 259. 
District : Port Erin. 
Zone: M.T. to H.W.O.N.T. 
Occurrence: Casual, Annual, Summer. 
Reproduction : Summer. 
Notes: Found in Petrocelis cruenta. 
Sub-Order. CONFERVOIDEAE. 
Fam. BLASTOSPOREAE, 
Gen. Prasiola, Ag. 
P. stipitata, Suhr. Locally abundant (see note 1, p. 105). 
Fig.: Plate XVI, 50. 
District: Port Erin; Peel; The Chasms; Port St. Mary. 
Zone: H.W.O.S8.T. 
Occurrence: Pseudo-perennial. 
Reproduction : Common throughout year. 
Notes: Found under rocks inhabited by sea-birds. 
Fam. ULVACEAE. 
Gen. Pringsheimia, Rke. 
P. scutata, Rke. Not uncommon. 
Fig.: Oltmanns I, p. 301. 
District: Port Erin; Port St. Mary; Fleshwick; Castletown. 
Zone: No definite zone. 
Occurrence : Sporadic, same as host. 
Reproduction : -All times. 
Notes: Epiphytic on many algae, e.g.: Polysiphonia, Ceramium, etc. 
