55 

 55 

 



440 D. J. SCOURFIELD ON A NEW COPEPOD. 



Fig. 4. First foot ? , x 6C0. 



5. Seta on inner angle of basal joint of first foot <$ . 



6. Fourth foot ?, x 600. 



7. Inner branch of fourth foot J 1 , x 1000. 

 8. Fifth foot ?, x 1000. 



9. ,, S, x 700. 



10. young ? (antepenultimate stage). 



11. $ (penultimate stage). 



12. Anal plate, young (three stages before adult). 



13. (penultimate stage). 



14. Last abdominal segment and furca from side ?/x 700, 



15. ,, ,, dorsal view ? , x 700, 



16. 3 ,, segments ,, ventral view (some- 

 what flattened and contracted), x 350. 



17. First and second abdominal segments, dorsal view ? y 

 X 350. 



18. Receptaculum seminis $, x 900. 



19. Spermatophore, x 400. 



20. Inner branch of second foot $ (from left side), x 500. 



21. third <?, x 500. 



5> 



J) 

 )) 

 >> 



55 



55 



Note added April 1915. 



A single individual of M. arboricola has now been seen carrying 

 an ovisac containing four eggs, the latter being almost perfect 

 spheres l/500th inch in diameter. The ovisac itself was very 

 delicate and soon became detached, and also separated into two 

 parts, each containing two eggs, by the movements of the animal 

 when lightly held in the live-box. 



Nauplii in various stages have also been seen. The earlier 

 forms exhibit a somewhat elaborate structure on the back, con- 

 sisting of three pairs of papillae with pointed tips lying between 

 two strong lateral thorns. Whether this is characteristic of the 

 species or not is unknown. 



Journ. Quekett Microscopical Club, Ser. 2, Vol. XII., N: 76, Ap 1915. 



