202 DISCOVERY REPORTS 



Lopadorhynchus krohnii (Claparede), 1870 

 Type locality. Naples. 



Hydrophanes Krohnii Claparede, 1870, pp. 464-6, pi. 11, fig. 2. 

 Hydrophones Krohnii Viguier, 1886, pp. 385-7, pi. 22, figs. 1-10. 

 Lopadorhynchus Viguieri Reibisch, 1893, p. 253. 

 Lopadorhynchus Viguieri Reibisch, 1895, pp. 37-8, pi. 4, fig. 4. 

 Lopadorhynchus viguieri Ehlers, 1913, p. 463. 

 Lopadorhynchus Krohnii Bergstrom, 1914, pp. 180-2, fig. 68. 

 Lopadorhynchus Krohnii Fauvel, 1923, pp. 185-6, fig. 6ga-d. 

 Lopadorhynchus Krohnii var. simplex Monro, 1930, p. 72, fig. 23. 

 Lopadorhynchus Krohnii var.. simplex Monro, 1936, p. 113. 

 Lopadorhynchus Krohnii Wesenburg-Lund, 1939, pp. 15-16, fig. n. 



Description. A large specimen of this species may measure 10-5 mm. long by 3 mm. wide for 

 twenty-three chaetigers, but normally the length varies between 5 and 7 mm. and the width is 2 mm. 

 for twenty to twenty-two chaetigers. The body is divided into two distinct regions at the posterior 

 border of the second chaetiger. The prostomium is twice as wide as long, with a rounded anterior 

 border and two long dorsal and two very short ventral antennae. No eyes have been seen in the 

 specimens examined. There are two pairs of elongate tentacular cirri. The first two chaetigers are 

 directed laterally and are shorter and stouter than the rest; they have simple hooked chaetae and a 

 dorsal cirrus but no ventral cirrus. The remaining parapodia are directed posteriorly and are thin and 

 lanceolate with small dorsal cirri and short ventral cirri; chaetae are compound, with heterogomph 

 articulation and serrated ovate terminal pieces, grouped fan-wise about the large lanceolate pedal lobe. 



Discussion. In the specimens examined no simple chaetae were present posterior to the first two 

 parapodia and in this respect the material differs from that widely reported from the Mediterranean 

 (Wesenburg-Lund, 1939). I do not consider, however, that this warrants the erection of a new 

 variety as Monro (1930) did in naming his material L. krohnii var. simplex. I find it identical with 

 L. krohnii. It may be significant, all my material and Monro's being larger than the European, that 

 simple chaetae may disappear with age and approaching sexual maturity, but clearly more material 

 than at present available is required to confirm this. 



General distribution. L. krohnii has been found at a number of stations in the South Atlantic where 

 it has its southern limit of distribution at the Sub-Tropical Convergence (see pp. 259-261). 



Genus Pelagobia Greff, 1879 



Prostomium with four antennae. Two pairs of tentacular cirri on the first chaetiger. Parapodia 

 uniramous with dorsal and ventral cirri cylindrical (dorsal cirrus reduced or absent on the second 

 chaetiger), with a chaetigerous mamelon, aciculae, and compound chaetae with denticulate terminal 

 pieces. Proboscis smooth, pygidium with two anal cirri. 



Type species. Pelagobia longicirrata Greeff, 1879. 



Type locality. Arrecife, Canary Islands. 



Pelagobia longicirrata Greeff, 1879 



Pelagobia longicirrata Greeff, 1879a, pp. 247-9, P^ I 4> fi g s - 2 3~5- 

 Pelagobia longocirrata Viguier, 1886, pp. 377-82, pi. 21, figs. 1-13. 

 Pelagobia longecirrata Reibisch, 1895, pp. 21-4, pi. 2, figs. 1-9. 

 Pelagobia longecirrata Reibisch, 1905, pp. 3-4, figs. 4-6. 

 Pelagobia longecirrata Southern, 1909, p. 2, pi. 1, fig. 1. 

 Pelagobia Viguieri Gravier, 1911a, p. 311. 



