58 On some new and rare Crustacea from Scotland. 



terer Maxillarfuss schmachtis;, niit einem Greifhaken versehen. 

 Furcalanlijiiige beim (^ und ? verschicdeu gestaltet. Zwei 

 Eiersiicke." 



Thalestris mysis, Glaus. 



This very distinct species was during the last summer 

 observed by us tor tlie first time in the Firtli of Forth. The 

 large foliaceous fifth pair of swimming-feet are closely and 

 obliquely striate, the striie being quite distinct. Thalestris 

 nu/sis appears to be comparatively rare in Britain; there are 

 few Scotch records for it, and its occurrence in the Forth is 

 therefore of interest. 



EXPLANATION OF THE PLATES. 



PLiTE V. 

 Leptopsyllwi intermedins, sp. ii. 



Fifj. \. Female, seen from tbe side, x 80 (A, front view of ovisac). 



2. Anterior antenna, X 500. 3. Posterior antenna, X 500. 



4. Mandible and palp, X 500. 5. Foot of first pair of swim- 

 niinfr-feet, X 380. 0. Foot of second pair, X 380. 7. Foot of 

 fourth pair, X 380. 8. Fifth pair, female, x 253. 9. Fifth 

 pair, male, X 253. 10. Abdomen and caudal stylets, dorsal 

 view, X 80. n. Male spermatophore, X 380. 



Mcsochra spinicmida, sp. n. 



Fif/. 12. Female, seen from the side, X 80. 13. Anterior antenna, female, 

 X 380. 14. Anterior antenna, male, X 380. 15. Posterior 

 antenna, X 380. 16. INIandible and palp, X 380. 1 7. Maxilla, 

 X 380. 18. Anterior foot-jaw, X 380. 19. Posterior foot-jaw, 

 X 380. 20. Foot of fir.~;t ])air of swimming-feet, X 380. 

 21. Foot of fourth pair, X 380. 22. P'oot of fifth pair, female, 

 X 380. 23. Foot of fifth pair, male (A, appendaj^e to first 

 abdominal ajipeudage), X 380. 24. Abdomen and caudal 

 stylets, dorsal view, x 80. 25. Male spermatophore, X 380. 



Mesochra Maclntoshi, sp. n. 



Fig. 26. Posterior foot-jaw, x 760. 27. Abdomen and caudal stylets, 

 dorsal view, X 80. 



Plate VI. 

 Mesochra Maclntoshi, sp. n. 



Fig. 1. Female, seen from the side, x 80. 2. Anterior antenna, X 253. 



3. Posterior antenna, X 253. 4. Mandible and palp, X 380. 



5. Foot of first pair of" swimming-feet, X 383. 6. Foot of fourth 

 pair, X 253. 7. Foot of fifth pair, x 380. 



Psettdoicestwoodia pygmcea, sp. n. 

 Fig. 8. Ftraale, seen from the side, X 80. 9. Anterior antenna, x 380. 



