201 
ments 4 to 9. One pair of cesophageal pouches, cylin- 
drical, club-shaped or conical. | Diaphragmatic pouches 
(on the first diaphragm) small, globular or flask-shaped. 
Found on both sides of the Atlantic north of 40° N. 
latitude. 
(0) A. asstmilis, Khlers.* Twenty chetigerous seg- 
meuts. Thirteen pairs of gills, the first of which is 
situated on the eighth segment (the first gill is Hable to 
be reduced or suppressed). Otocysts large, opening to the 
exterior. Otoliths numerous, spherical or rounded 
chitinoid bodies. Six pairs of nephridia opening on seg- 
ments + to9. Several pairs of cesophageal pouches; the 
anterior pair long, club-shaped or filiform, the others 
much smaller and pear-shaped. | No pouches on the first 
diaphragm. . 
Recorded from the extreme south of the American 
continent. 
(c) A. assimilts, var. affinis, Ashworth.” Nineteen 
cheetigerous segments. Thirteen pairs of gills, the first 
(liable to reduction or suppression) on the seventh seg- 
ment.  Otocysts large, opening to the exterior. Otoliths 
numerous, and composed either of foreign bodies (quartz 
erains, &e¢.), or of spherical chitinoid bodies. Other 
characters as in the type of the species (see above). 
Recorded from Otago Harbour, New Zealand, the 
Macquarie Islands, the Falkland Islands. 
(d) A. claparedii, Levinsen.t Nineteen cheetigerous 
segments. Thirteen pairs of gills, the first on the seventh 
segment (this pair of gills is liable to reduction or sup- 
pression especially in specimens from the west coast ot 
North America). Lateral lobes of prostomium well 
** For an account of these forms see Ashworth, J. H.—Q.J.M.S., 
Vol. 46, pp. 737-785. Pls. 36-37. 
+ For an account of these species see Gamble, F’. W. and 
Ashworth, J. H.—Q.J.M.S., Vol. 48, pp. 419-569. Pls. 22-29. 
