1897.] PLANKTON or THE FAEEOE CHANNEL. 525 



the second cirrhi (Borstencirrhen) were only 33 mm. long in this 

 specdmen, but in smaller ones were often longer than the body. 

 The fully developed parapodia were 20 in number ; the undeveloped 

 posterior part of the body carried eight rudimentary parapodia, 

 and measured 9 mm. In the youngest specimens the parapodia 

 were proportionately fewer than in the medium-sized specimens, 

 and are again less crowded in the largest. Points like these, taken 

 with the specific uncertainty already discussed, show how necessary 

 is a renewed study of the genus on living material. 



I have not found any record of a larger specimen than this, 

 but my friend Mr. E. T. Browne informs me that he has taken a 

 specimen about 55 mm. in length off Valentia. 



As regards the horizontal distribution of the species, it is 

 common in northern seas, but not apparently further north 

 than the Taeroe Channel. Here it was captured by both the 

 ' Knight Errant ' and the ' Triton,' and Prof. M'Intosh ^ points 

 out that it appears to have been procured from very varying 

 depths ; this agrees with ray experience on the ' Research ' ; it was 

 taken at" Sta. 13*7 — 465 to 335 fathoms, temp. 31° to 33^ Eahr., 

 and was also taken at the surface at a temperature of 54° F. 



Tkacheloteuthis biisbi (Steenstrup). 



I have found some difficulty in the determination of this species, 

 owing probably to the fact that Steenstrup's original description ' 

 was of the briefest. 



A specimen obtained in the Eaeroe Channel during the cruise of 

 H.M.S. ' Knight Errant ' in 1880 was fully described by Hoyle 

 among the ' Challenger ' Cephalopoda ^ but he expressed himself as 

 uncertain of his determination. 



The deciding characteristics of the only two species ' known 

 appear to be the following according to Carus " (founded on Hoyle 

 and Weiss) and Steenstrup : — 



riisei. hehnii. ' Eesearcli ' spec. 



Fins Ehomboid. C, S. Eounded behind. C. Eounded behind. 



Heart-shaped. S. Heart-shaped. 



=5 body length. C. >;j body length. C' —\ body length. 



—\ body length. S. 



Tentacles =body length. 0. =| body length. C. =body length. 



Arm 4 . . . = f length of arms 2, 3. S. = ^ length of arms 2, 3. S. = | length of 2, 3. 



While, then, the general dimensions of my specimen agree wdth 



1 ' Challenger ' Eep. Zool., Annelida Polychaeta, xii. p. 532. 



•"■ Cf. Proc. Zool. Soc 1896, p. 993 note. 



^ Vidensk. Medd. Nat. Foren. Kjobenhavn, (4) iii. p. 293. 



■* Ohall. Eep. Zool. xvi. Cephalopoda, pp. 1G3-166, pi. xxviii. figs. 6-12. 



' Since the above was in type, I find that a third species, T. gugrnei, has 

 been described by Joubin (' Oampagnes Scientiflques par S. A. le Prince de 

 Monaco,' fasc. ix.), but it is not likely to be confounded with either of the other 

 two. 



" Prodrom. Faunae Mediterr. ii. pp. 447, 448. 



'' " Plus quam ^ pallii sequantes." Surely a mistake ! 



Proc. Zool. Soc— 1897, No. XXXV. 35 



