46 PKOF. M. M. IIAKTOG ON THE MORPHOLOGY OF CYCLOPS. 



the incomplete circular muscles in fascicles attached at the sides of the gut, and diverging 

 towards the upper (and lower) median line ; the striation is too marked, and the longitudinal 



fihres are omitted. E. 

 Fio-. 1. Sagittal section (almost exactly median) through front of eephalon, showing relations of rostrum, 



epistoma, and labrum, a3sopliagus, and muscles of deglutition, brain with azygos nerve and 



ganglion, eye, and nerve-cord. x 150 : C. 

 Fig. 5. Transverse section of maxillary region of male (slightly diagrammatized), and the anterior branches 



of the uterus, introduced from a corresponding section of a female, showing muscles of maxilla, 



position of entosternitc with its suspensors, retractors of preoral bar, nerve-cord, stomach, and 



pleural muscles, &c. X 150 : C. 

 Fig. 6. Horizontal section of front of cephalon of female, showing relations of mouth, &c., salivary glands, 



and duct. X 150 : C. 

 Fig. 7. Left kidney of immature female, in natural position, from without, shaded to convey relations 



of its successive coils : 1, point at which it bends inwards (into ccelom ?) ; 2, commencement 



of duct. X 250 : D. 

 Fig. 8. From a transverse section in the region of the anterior maxillipeds, showing relations of kidney 



and duct : 1, 2 as in Fig. 7. x 125 : D. 

 Fig. 9. Left kidney of Nauplius, 2nd stage, in situ, from below, with its termination (opening ?) on base 



of antenna, and its other end in a mass of protoplasm in the body, x 525 : J. 

 Fio'. 10. Series of maxillae from various Copepoda, to show transitional forms from biramous condition to 



that of the Phyllopod (copied by kind permission from Brady's 'British Copepoda') : — 



a. CaJanus finmarchicus, Gunner _; b. Metridia armata, Boeek ; c. Pseudocahnius armatus, 



Boeck ; d. PonteUa Wollastoni, Lubbock ; e. Pseudoctj clops obtusatus, Brady and Robertson ; 



/. Parapontella brevicornis, Lubbock ; g. Notodelphis agilis, Thoi'cll ; h. Robertsonia tenuis, 



Brady and Robertson. 



Plate IV. 



Fig. 1. Sagittal section o anterior part of nerve-cord, traversed by retractors of preoral bar. x 375 : E. 

 Fig. 2. Horizontal section of nerve-cord in region of first and second maxillae, showing transverse fibres, 



slightly deeper on left side, x 375 : E. 

 Fig. 3. Superficial view of brain, from a dissection (osmic acid, cochineal, oil of cloves), with origin of 



nerve to left antennule, forming a lateral lobe, x 250 : D. 

 Fig. 4. Sagittal section of brain and eye to left of median line, showing left superior frontal nerve. 



X 250 : D. 

 Fig. 5. Sagittal section of eye, nearly median, x 525 : J. 

 Fig. 0. Slightly oblique section of eye. x 375 : E. 

 Pig. 7. Horizontal section of inferior (median) ocellus, x 375 : E. 

 Fig. 8. Dissection (after gold chloride) of front of brain and eye. x 250 : D. 

 Fig. 9. Transverse section of nerve-cord in posterior region of first maxillse. x 375 : E. 

 Fig. 9 a. Section at level of posterior maxillipeds ; all nerve-cells alone indicated, x 150 : D. 

 Fig. 10. Portion of large nerve-trunk laid open by razor, and showing nucleoid granules. x 525 : J. 

 Fig. 11. Expansion of a large nerve (sensory, below hypoderm). (From a transverse section.) 

 Fig. 12. Doyerian eminence, from same section as fig. 11. x 375 : E. 

 Fig. 13. A nucleus from posterior end of testis (rhachis) : b, dividing nuclei from a little further on, one 



showing the diaster stage, with spindle of achromatin fibres ; c, male ova, or spermatosporcs 



from about middle of testis; d, male ova, with dividing nuclei, from a little further on. (All 



these taken from a dissection treated as in fig. 3.) x 1050 : J. 

 Fig. 14. Expidsive bodies from a crushed seminal vesicle, slightly swollen (Draper's ink, glycerine). 

 X 750 : E. 



