BLOOD-PAJBASITES OF FISHES OCCURRING AT ROVIGNO. 153 



21. Sambon, L. W., and Seligmann, C. G. — " The Haemogregarines of 



Snakes," ' Trans. Patli. Soc.,' Iviii, 1907, p. 310, with plates. 



22. "Wenyon, C. M.—" Report of Travelling Protozoologist," 'Rep. 



Wellcome Res. Lab.,' iii, 1908, p. 121, with j)lates. 



23. Woodcock, H. M.— " On the Occnrrence of Nuclear Dimorphism in 



a Halteridium Parasitic in the Chaffinch, etc.," 'Quart. Journ. 

 Micr. Sci.,' 53, 1909, p. 339, with figs. 



EXPLANATION OP PLATES 8-10, 



Illustrating Professor E. A. Mincbin's and Dr. H. M. Wood- 

 cock's paper on " Observations on certain Blood-parasites 

 of Fishes occurring at Rovigno." 



[The drawings on PL 8 are all from Giemsa-stained preparations, 

 those on PL 9 are from films stained with iron-hsematoxylin, and those 

 on PL 10 from films stained by Twort's method. All the figures relat- 

 ing to H se m o g r e g a r i n a r o v i g n e n s i s are magnified 3000 times linear ; 

 those relating to Trypanosoma triglse and T. raise 2000 times.] 



PLATE 8. 



Figs. 1-28. — HsBinogregarina rovignensis. Pigs. 1-11 are from 

 the first infected gurnard, figs. 12-27 from the second, and fig. 28 from 

 the third infected fish. Figs. 5-11 are from a very thin smear, which 

 was faintly stained ; both corpuscles and parasites are uniformly flattened 

 out, but the nuclei of the parasites come out better than in any other 

 Giemsa-stained smears. 



Fig. 1, 2, 5-9, 16, 17. — Ordinary small forms, schizonts. 



Fig. 3. — A small form, free from the blood-corpuscle, occurring 



in a smear from the kidney. 

 Figs. 4, 10, 18-21. — Large forms of the slender or male type. 

 Figs. 11, 22-26. — Large forms of the broad or female type. 

 Figs. 12, 13. — Young individuals of the slender, male type. 

 Figs. 14, 15. — Young and intermediate-sized individuals respec- 

 tively of the broad, female type. 

 Fig. 27. — A double infection of the corpuscle, with two small 



forms of the parasite. 

 Fig. 28. — Small form showing a constriction of the nucleus in the 

 middle. 



