FLUSTRA. 19 



There is another product which, if not to be identified with the pre- 

 ceding, may be a variety. Besides having fewer subordinate parts, the 

 only difference I have hitherto observed, consists in the greater breadth 

 of the leaf in proportion to its height. Specimens are rare — one rose an 

 inch and a half. It was broad above, like that represented by Ellis, 

 Plate xxix. fig. 2. 



Plate III. — Flustra foliacca. 



Plate IV. Fig. 1. Hydrse protruding from opposite sides of the leaf. 



2. Colls. 



3. Fei - ruginous patch on a leaf. 



4. Group of corpuscula swimming at the surface of the water. 



5. Group of corpuscula more enlarged. 



6. Corpuscula of various configuration magnified. 



7. Corpuscula stationary, with an originating prolongation. 



8. Corpusculum stationary ; prolongation advancing. 



9. Nascent Flustra with originating leaves. 



10. Nascent Flustra farther advanced. 



11. Nascent Flustra with a young hydra. 



12. Nascent Flustra advanced still farther, the original hydra 



having decayed. 



13. Margin of a leaf. 



All the figures of this Plate are enlarged. 



§ 3. Flustra teuncata. — Plates V., VI. — In as far as I have seen, 

 the subject of this paragraph is the most luxuriant of the genus Flustra 

 occurring in the Scotish seas. Its resemblance is so great to vegetable 

 foliage, that, from this alone, a cursory observer would incline to remove 

 it from the animal kingdom. But the myriads of sensitive, vivacious, 

 active creatures united to the inorganic parts, determine its true posi- 

 tion. 



The Flustra truncate rises erect to the height of five inches, by a short, 

 narrow, flattened stem, and diverges five or six inches by subordinate 

 leaves and leaflets. According to dimensions, age, and place, it appears 



