564 



DR S. F. HAEMER AND DR W. G. RIDEWOOD ON THE 



(06) RiDEWOOU, W. G., "A New Species of Ceplialodiscus {C. gilchristi) from the Cape Seas," Marine 

 Incestigations, South Africa, iv., Cape Town, 1906, pp. 173-192, three plates and five text-figures. 



(07^) " Pterobranchia : Ceplialodiscus,^^ National Antarctic Expedition: Natural History, vol. ii., 



London [Brit. Mus.], 1907, pp. 1-67, seven plates and seventeen text-figures. 

 - " On the Development of the Plumes in Buds of Ceplialodiscus" Qvart. Journ. Micr. Sri., 



(072) 

 (12) 



N.S., li., 1907, pp. 221-252, eleven text-figures. 



- "On Specimens of Ceplialodiscus nigreseens supposed to have been dredged in 1841 or 1842," 

 Ann. Mag. Nat. Hist. (8), x., Nov. 1912, pp. 550-555, one text-figure. 

 (05) SoHEPOTiEFF, A., " Zur Organisation von Ceplialodiscus," Bergens Museums Aarbog, 1905, No. 8, 



pp. 20, two plates. 

 (07) "Die Pterobranchier : Anatomie von Ceplialodiscus," Zool. Jahrb., Abtli. ficr Ajiat., xxiv., 1907, 



pp. 553-608, eleven plates. 

 (08) " Die Pterobranchier : Knospungsprozess von Cephalodiscus, und vergleichend-anatomischer Teil," 



Zool. Jahrb., Ahth. fiir Anat., xxv., 1908, pp. 405-491, four plates. 

 (09) "Die Pterobranchier des Indischen Ozeans," Zool. Jahrb., Abth. filr Sgstematik, xxviii., 4, 1909, 



pp. 429-445, two plates. 

 (12; Spbngel, J. W., "Pterobranchia," in Handioorterbucli der Naturwissenscliaften (Korschelt and others), 



vii., 1912. 



LIST OF REFERENCE-LETTERS. 



an., anus. 



b.c.^, proboscis-cavity. 

 b.c.'^, collar-cavity. 

 h.c.'^a., anterior dorsal horn of collar-cavity. 



b.c.^, metasomatic cavity. 

 b.c.^b., part of metasomatic cavity in loop of ali- 

 mentary canal. 

 c.c, collar-canal. 

 c.c.i., internal opening of collar-canal. 

 c.n.s., central nervous system. 

 d.m.^, dorsal mesentery of collar. 

 d m?, dorsal mesentery of metasome. 

 g.s., gill-slit. 

 int., intestine. 

 L.i-L.^, left arms. 

 l.n., lateral nerve. 

 TO., mouth. 

 ms., longitudinal muscles of metasome. 



nch., notochord. 

 n.t., nerve-tract. 



op., operculum or postoral lamella. 

 op.l., left lobe of operculum. 

 op.r., right lobe of operculum. 

 op.rec, recess at base of operculum. 

 p., proboscis. 

 per., peristome. 

 2^h., pharynx. 

 p.p., proboscis-pore. 

 r., rectum. 

 R.1-R.9, right arms. 

 St., stalk. 

 stom., stomach. 

 t., testis. 

 t.L, left testis. 

 t.r., right testis. 

 v.m.^, ventral mesentery of collar. 



