Plate 6. 

 Figs. 24, 25. Argyropeleciis lychiius Gannau. 



Fig. 24. Axiiil section vertical tu the median plane of the lish through au anterior lateral 

 radiating organ. Stained: picric acid-carniin. Drawing; magnified 1 : iH. A, 

 proximal oval part of the organ; B, zigzag fibres of the reflecting layer; G, 

 constriction between the [iroximal and distal part of the organ ; 1), distal para- 

 boloidal part of the organ; g, inner region; 1, middle region; p, pigment 

 sheath; r, reflecting layer; s, outer region. 



Fig. 25. The fish seen from the side. Drawing; natural size, a, anal radiating organs ; 

 al, anterior lateral radiating organs ; ao, anteorbital radiating organs ; lir, 

 branchiostegal radiating organs; ml, medial lateral radiating organs ; op, oper- 

 cular radiating organs ; pc, pectoral radiating organs ; po, postorbital radiating 

 organs; vc, ventrocaudal radiating organs ; ve, ventromedial radiating organs ; 

 vt, veutrothoracic radiating organs. 



Figs. 2G, 27. .Sternoiityx obscura Garman. 



Fig. 26. The fish seen from the side. Drawing; natural size, a, anal radiating organs; 

 al, anterior lateral radiating organs ; br, branchiostegal radiating organs ; op, 

 opercular radiating organs ; pi, posterior lateral radiating organs ; vc, venti-o- 

 caudal radiating organs ; ve, ventral radiating organs ; vt, veutrothoracic radi- 

 ating organs. 



Fig. 27. Axial section vertical to the median plane of the fish through a veutrothoracic ratli- 

 ating organ. Stained: haematoxylin-i)icri(^ aciil-fuchsin. Drawing; magnified 

 1 : 42. g, inner region ; gl, gelatinous tissue occupying the distal part of the 

 organ ; 1, middle region ; p, pigment sheath ; r, reflecting layer ; s, outer 

 region. 



Figs. 28-30. Cyclothoue aeclinidens Garman. 



Fig. 28. The fish seen from the side. Drawing; natural size, a, ventroanal radiating 

 organs: ve, ventromedial radiating organs; vt, veutrothoracic radiating organs. 



Fig. 211. The fish seen from below. Drawing; natural size, a, ventroanal radiating organs ; 

 br, branchiostegal radiating organs; vc, ventromedial radiating organs; vt, 

 veutrothoracic radiating organs. 



Fig. 30. Axial section vertical to the median plane of the fish through a veutrothoracic 

 radiating organ. Stained: haematoxylin-picric acid-fuchsiu. Drawiug; magni- 

 fied 1 : 520; b, blood vessel leading to the organ; c, connective-tissue capsule 

 within the pigment sheath; cd, trans|)arent connective tissue forming the super- 

 ficial covering of the organ in the orifice of the pigment sheath ; cr, distal part 

 of the connective-tissue capsule covering the mass of radiating cells outside ; 

 1, cylindrical cells of the outer zone ; m, central part of the organ composed of 

 small irregularly arranged polyedrical cells ; p, pigment sheath ; r, outer part 

 of the organ composed of cells arranged in regular rows ; t, transparent inter- 

 mediate zone. 



