NOTE ON TWO UNRECORDED PLUMULARIAN HYDROIDS. 261 



Outer Western Area of the Channel at Station 37 (S. 41° W. of Eddystone 

 at distance of 17*1 miles) in 190G. 



The other species is Antenella siliquosa (Hincks), described by Hincks, 

 from St. Peter's Port, Guernsey, in 1877,* and since recorded from only 

 two areas : from S.W. of Toulon at a depth of 445 metres, and in 

 the neighbourhood of RoscofE on the N.E. corner of France between 

 60 to 80 metres (Billard, 1907 and 1912). To these localities Plymouth 

 material adds two more records, both in the Outer Western Area of the 

 Channel. A few colonies were obtained from Station 80, S. 16|° W. of 

 Eddystone, 48-9 miles distant, at a depth of 51 fathoms ; and a larger 

 clump was dredged during Cruise VII at an undefined position between 

 S. 17° to 27° W. of the Eddystone, at a depth between 49 and 53 fathoms. 



The two species may be readily distinguished. Both have simple 

 unbranched stems. A. secundaria closely resembles P, catharina in the 

 details of structure, but has only one sarcotheca flanking each hydro- 

 theca, in place of a pair ; A. siliquosa has a wider and larger hydro- 

 theca, but its distinctive feature lies in the lateral sarcothecse, which 

 occur one on each side of a hydrotheca, and have the even margin of the 

 terminal section interrupted by a large wide embayment, a condition 

 not recorded from any other species of Antenella. 



* Aim. Mag. Nat. Hist., ser. 4, Vol. XIX, 1877, p. 148, PI. 12, Figs. 2-6. 



