THE OHKOJIATIN MASSES OF PIHOPLASMA BIGEMINUM. 297 



On the Chromatin Masses of Piroplasma 

 bigeniinum (Babesia bovis), the Parasite 

 of Texas Cattle-Fever. 



By 

 II. B. Fantlinni, B.Sc.LoikI., A.R.€.8., 



University College, London, and St. Mary's Hospital Medical School. 



With Plate 18, and 41 Text-figures. 



Contents. 



PAGE 



I. Introduction . . . . . .297 



II. Methods ...... 299 



III. Previous observations on the Chromatin of Piroplasma 



bigeminuni and P. can is . . . . 300 



IV. The Chromatin Massesof P. bigemiuum in (a) double 



pyriform, (/3) double ovoid, (y) single pyriform, (S) 

 rounded, («) groups of more than two, (K) dividing, and 

 (>/) other intra-corpuscular forms; also in (0) free 

 parasites ...... 302 



V. Note on the Cytoplasm of P. bigeminum . . 317 



YI. The Probable Significance of Nuclear Dimorphism in 



Piroplasma ...... 318 



VII. Summary of Results ..... 320 



VIII. References to Literature .... 323 



IX. Explanaiion of Plate . . . . .324 



I. Introduction. 



Some time ago, while looking at a preparation of Piro- 

 plasma bigeminum lent to me for examination, I was at 

 once somewhat surprised to find that many of these very 

 small parasites distinctly exhibited what has been called 

 " nuclear dimorphism/' for quite typical and non-dividing 



