060 DESCRIPTION OF PLATES, 23, 24. 



Fig. 5 l , first segment of body, homologically the last or seventh 



cephalic segment. 

 2 , second segment of body, homologically the first thoracic 



segment. 

 8 , third segment of body, homologically the second thoracic 



segment. 



4 , fourth segment of body, homologically the third thoracic 

 segment. 



5 , fifth segment of body, homologically the fourth thoracic 

 segment. 



6 , sixth segment of body, homologically the fifth thoracic 

 segment. 



7 , seventh segment of body, homologically the sixth thoracic 

 segment. 



8 , eighth segment of the body, homologically the seventh 

 thoracic segment. 



6. Front of mouth ; g, outer maxillae ; g\ an articulation sepa- 



rating the mouth from the membrane of the first segment 

 of the body ; h, first pair of maxillipeds ; whole figure on 

 same scale with the labrum, fig. 9. 



7. Maxillae, drawn on thrice the scale as the outer maxillae ; 



a, apodeme. 



8. Mandibles, drawn on thrice the scale as the outer maxillae. 



9. Labrum, on same scale with the outer maxillae, fig. 6, and 



one third of the scale of the mandibles and inner 

 maxillae; e, labrum ;f, palpi. 



PLATE 24. 



Cryptophialus minutus. 



Fig. 10. Lower enlarged end of oesophagus, where entering the 

 stomach, viewed from one of the sides bearing the discs 

 of teeth ; a, upper cut off end of oesophagus ; b, the lower 

 end and natural opening ; c, thickened rim, having a some- 

 what beaded structure. 



1 1 . The same ; diagram giving a transverse section of the above 



in the line of the discs of teeth ; c c c c, four thickened 

 beaded edges ; e e, two other but narrower and less pro- 

 minent beaded edges ; d d, discs of teeth ; f, rows of fine 

 bristles ; the almost double row of bristles on each side 

 under (d) is not of course seen in this section. 



12. Lower end of oesophagus viewed from a position at right 



angles to that in fig. 10; or from the side e, of the 

 diagram, fig. 1 1 ; the two discs of teeth are consequently 

 shown in profile ; a, upper cut off end of oesophagus ; 

 b, lower natural end ; c, c, thickened edges ; e, narrower 

 thickened edge, projecting towards the beholder ; d, disc 

 of teeth seen in profile. 



13. Portion of one of the cirri; a, lower segment of pedicel; 



b, upper segment, supporting the two rami. 



