THE PENNATULIDA DREDGED BY H.M.S. " PORCUPINE." 459 



The calcareous axis extends quite to the lower end of the stalk, where it is 

 hooked : it measures "15 mm. in diameter at its widest part. 



The following table gives the dimensions of the leaves in this specimen, the 

 proportions of which may be taken as typical for all the four : — 



2 autozooids, length 3 - 9, l - 9 mm. 

 4-0, 2-5 mm. 

 4-3, 3-2, 2 mm. 

 45, 3-3, 2 mm. 



3 autozooids, length of leaf, 4 - 2 mm. 



4-0 „ 

 3-0 „ 

 2-4 „ 

 1-9 „ 

 1-9 „ 



Pairs 6-9 have the form of obliquely placed ridges, in which no truly formed 

 autozooids are discernible. 



The general dimensions of the four specimens are as follows : — 



ir 1. Left leaf, 



. 2 



Eight „ 



2 



2. Left „ 



. 3 



Eight „ 



. 3 



3. Left „ 



. 3 



Eight „ 



. 3 



4. Left „ 



. 3 



Eight „ 



o 



O 



5. Left „ 



o 

 O 



Eight „ 



. 3 





A. 



B. 



C. 



D. 



Length of specimen, 



. 20 mm. 



21 mm. 



19 mm. 



23 mm 



jj SLRlKj ■ • 



9 „ 



10 „ 



9 „ 



11 „ 



„ rachis, 



11 „ 



11 „ 



10 „ 



12 „ 



„ longest leaf, 



5 „ 



3-5 „ 





4-3 ,, 



Diameter of rachis, 



•6„ 



11 „ 



11 „ 



•85 „ 



Number of pairs of leaves, . 



5 



5 



4 



5 



These four specimens are, we believe, the youngest that have yet been 

 described: the presence in each of them of a large terminal autozooid, with an 

 unusually large siphonozooid at its base, is of very considerable interest, and 

 affords strong reason for holding that the mode of formation of the colony in 

 Pennatula is similar to that described by Wilson for Renilla {Phil. Trans., part 

 iii. 1885). 



Subsection ii. Virgulariece. 

 Family 1. Virgularidae. 



Genus Svava (Kor. and Dan.). 

 Svava glacialis, var. alba (Kor. and Dan.). 



One fragment of this interesting form, 6*5 cm. in length, was taken in 

 1869 at Station 1, comprising the rachis cut off just at its junction with the 

 stalk, and incomplete above. The autozooids, three or four of which go to 

 form a leaf (except at the highest part of the rachis, where there are two only 



