1898-1902. No. 13.] ECHI NODERMATA. 19 



March 7, 1900. Bay south of Sjopolse Ness; 30—40 m. Stones & 



laminaria. 

 June 26, 1900. The rock in Havne Fjord; about 10 m. Stones with 



calcareous algae. 

 July 21, 1900. Winter harbour, Havne Fjord; about 60 m. Small 



stones with calcareous algae. 

 July 22, 1900. Winter harbour, Havne Fjord; about 60 m. Small 



stones. 

 July 22, 1900. Winter harbour, Havne Fjord; about 16 m. 

 July 23, 1900. Winter harbour, Havne Fjord; about 40 m. 

 July 26, 1900. West side of the mouth of Stor Valley; about 20 m. 



Clay. 

 July 29, 1900. South-east of Breakfast Point; about 30 m. Stones. 

 July 80, 1900. Mouth of Stor Valley. 

 Aug. 1, 1900. Mouth of Stor Valley; up to 20 m. Small stones 



with some clay. 

 Aug. 1, 1900. Mouth of Stor Valley; 60-4 m. Small stones. 

 Aug. 4, 1900. Sjopolse Ness; 50 — 30 m. Small stones. 

 Aug. 8, 1900. Winter harbour, Havne Fjord; about 30 m. 

 June 28, 1901. Mouth of Hvalros Fjord. 

 June 29, 1901. Off the camping-ground. 

 July 5, 1901. The Sound. 

 July 8, 1901. Ren Bay. 

 July 9, 1901. Ren Bay. 

 July 12, 1901. Bay at Land's End. 

 July 19, 1901. Gaase Fjord. 

 July 11, 1902. St. Helena; 14—4 m. 

 July 19, 1902. North Devon, off the camping-ground; 14-6 m. 



The disc in the largest specimens is from 10 to 12 mm. in dia- 

 meter. On two of the arms of a 10 mm. specimen with no statement 

 of the locality, some of the dorsal and ventral plates are bipartite. Two 

 of its mouth-shields also are divided, one into two, the other into three, 

 unequal parts. The specimen is moreover characterised by numerous 

 papillae — as many as 25 in each group — at the arm-notches 



(figs. 9, 10). 



In the diagnosis of the species, OpMura robusta is said to have 

 only one tentacle-papilla; but this refers only to the distal brachial 

 joints. It is not unusual to find two papillas, sometimes indeed even 4 

 or 5 (see Lutken, 25, p. 46) at the innermost tentacle-pore. Where 



