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ON CARRAGEEN. CHONDRUS CBISPUS. 



By PAUL HAAS and T. G. HILL. 



Botany Department, University College, London. 



(With 5 Text-figures.) 



The scarcity of gelatine during the period 1915-1919, and in many cases 

 its poor quality, led those concerned to seek for a substitute, with the 

 result that carrageen once more came back to favour. In this respect 

 Mrs Maitland Malcolm was most active; the Ministry of Food expressed 

 its approval of "Irish moss" in the preparation of invalid foods, and its 

 collection was organised by the Food Production Department. The 

 observations made by various members of the British Red Cross Society 

 have thus led to a revival of interest in the plant, and at the instance of 

 Professor Oliver we undertook its examination. It has been considered 

 desirable to publish this preliminary general account for the use of those 

 concerned not with the chemistry of the substance but with its value as 

 food and in the arts, and to reserve for a future occasion our observa- 

 tions, as yet incomplete, on the more purely scientific aspects of carrageen. 



Chondrus crispus, Lyngb., is a member of the Gigartinaceae, a family 

 of the Florideae (red seaweeds), and is widely distributed on rocky 

 sea shores. In the British Isles it is abundant on the west coasts of 

 Ireland and Scotland and on the south and north-west coasts of Wales. 

 In England it is reported from the south-west — Dorset, Devonshire, 

 particularly the south coast, Cornwall and Somerset — and from North 

 Yorkshire and Northumberland. It extends from three-quarters tide 

 level to below low water mark and favours sloping localities, especially 

 where the rocky shore gently slopes to low water mark. 



Chondrus crispus is a perennial plant which reaches its maximum 

 vegetative development in spring and summer. It is characterised by a 

 tufted habit, the fronds, narrow, flat and stalk-like basally, branching 

 distally into flat or curled expansions, varying in colour from purple 

 brown to red purple in more strongly illuminated situations. Iridescence 

 is a characteristic feature . The reproductive organs are immersed in the 

 fronds. 



