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“PLANTULE 
Fic. 1. The Life-Cycle of Aspevococcus fistulosus. 
4. Minute Ectocarpr. 
In dealing with minute ectocarpoid epiphytes it is 
essential to know whether the basal layer of the plant is a 
plate formed of radiating filaments with more or less lateral 
coherence or whether the upright filaments arise from a 
branching system of horizontal threads that may be 
intricately tangled but do not form a_ pseudo- 
parenchymatous disc. 
To decide this point it is useful to study young plants 
before the upright filaments make their appearance. li 
no young stages are available an inspection of the margin 
of the plant will sometimes provide information. 
Care must be taken to discriminate between young 
stages of the larger species of Ectocarpus and mature 
individuals of minute species of Ectocarpus associated 
genera such as Séreblonema, etc. The latter have an 
extensive photosynthetic horizontal thallus which makes 
up the dominant part of the thallus ; erect filaments are 
small and for the most part concerned with reproduction. 
Young stages of larger species have a basal system of pale- 
coloured or colourless rhizoidal filaments of almost in- 
significant stature when compared with the sturdy erect 
filaments that may grow to considerable size before they 
shew signs of reproduction. 
5. Leptonema fasciculatum, Rke. var. majus Rke. 
Plants answering to the description given by Reinke 
(Atlas deutscher Meeresalgen) were found in the lobster 
