CHAETOGNATHA COLLECTED BY STEAMER ALBATEOSS. 



267 



The six specimens were all obtained November 6, 1908, in the 

 China Sea in the vicinity of Formosa, at station D. 5320, 20 58' 

 north and 120 3' east by an open 0000 grit-gauze net towed at 3.18 

 p. m. in 500 fathoms for 20 minutes. 



EUKROHNIA RICHARDI Germain and Joubin. 



Plate 36, fig. 10; plate 37, figs. 15, 26. 

 Eukrohnia richardi GERMAIN and JOUBIN (1912), p. 2. 



This species (pi. 36, fig. 10) is represented by five specimens, only 

 two of which are well enough preserved to permit certain identifi- 

 cation. Measurements of these two (a and 6), and, for comparison, 

 those taken from Germain and Joubin's drawing (c), are as follows: 



It is questionable whether this species is valid or not. It closely 

 resembles E. hamata, but according to Germain and Joubin (1912, 

 p. 5), "il s'en distingue facilement, en dehors de sa coloration verte 

 caracte"ristique et jusqu'a present absolument unique chez tous les 

 Chetognathes, par la forme tres diff e"rente de sa tfite, beaucoup plus 

 nettement triangulaire allong6e, par ses crochets plus e'troitement 

 allonges et par ses dents, au nombre de 24, alors qu'on en compte 

 seulement de 20 a 22 chez I' Eukrohnia liamata" Of these distinc- 

 tive features it is evident that differences in the number of teeth 

 and shape of head are of no specific value, and it seems probable 

 that the color, which is described (p. 2) as "d'un vert d'eau plus 

 fonce a la region ante"rieure et s'attenuant re'gulierement vers la 

 queue," is also highly variable. In the Philippine material at least, 

 specimens of E. hamata agree quite as well with this description as 

 those of E. richardi. Both, although considerably faded by action 

 of the f ormalin, are dark green and more so anteriorly than posteriorly. 



Again, the various dimensions of the body recorded by Germain 

 and Joubin (p. 4) do not agree with those taken from the drawing. 

 The drawing measures 139 mm. in length. Assuming the recorded 

 length of 27 mm. to be accurate, the magnification of the drawing 

 is 5.15. This makes the length of tail 6.8 mm., or 25.2 per cent of 



