162 EDWIN 8S. GOODRICH 
EXPLANATION OF PLATES 5 AND 6. 
Fig. 1.—Young egg of Arenicola with small trophozoite inside it. Whole 
preparation ; Formol-iodine, Paracarmine. x 500. 
Fig. 2.—Later stage showing opening in vitelline membrane, and depres- 
sion in egg in which lies the parasite. Whole preparation; Formol- 
corrosive, Paracarmine. x 500. 
Fig. 3.—Nearly full-grown parasite in egg ; from the living. x 500. 
Fig. 4.—Semi-diagrammatic optical section of egg with contained para- 
site. x 500. 
Fig. 5.—Trophozoite emerging from egg ; from the living x 500. 
Fig. 6.—Portion of a section of an infected egg showing the young 
trophozoite. Bouin, Iron-Haematoxylin, x 1.100. 
Fig. 7.—Optical section of whole preparation of egg with full-grown 
trophozoite. Formol-corrosive-acetic, Paracarmine. x 500. 
Fig. 8.—Infected egg from which the parasite has escaped. Leucocytes 
are making their way into the cavity. From the living. x 500. 
Fig. 9.—Portion of a section of full-grown trophozoite which is fixed to 
host-cell near flattened nucleus, and showing deeply-staining bodies, a. 
Chrom-osmic ; Iron-haemat., Light-green. x 1,100. 
Fig. 10.—Part of section of uninfected egg, showing normal development 
of vitelline'and subvitelline membranes. Bouin, lron-haemat. x 1,100. 
Fig. 11.—Section of an infected egg from which parasite has escaped. 
Chrom-osmic ; Iron-haemat. x 500. 
Fig. 12.—Similar egg at later stage showing its destruction by invading 
leucocytes. Chrom-osmic, Iron-haemat., Light-green. 
Fig. 13.—Two Gonospora minchinii in association. Whole pre- 
paration. x 120. 
Fig. 14.—Section through dovetailing epimerites of associates. Chrom- 
osmic ; Iron-haemat., Light-green. x 1,100. 
Fig. 15.—Spore with eight sporozoites. x 3,000. 
REFERENCE LETTERS. 
a.=deeply-staining bodies at edge of trophozoite fixed to ovum. c¢.= 
cytoplasm of ovum. cp.=cytoplasm of parasite. /.—leucocyte in cavity 
vacated by parasite. /i.=limit between associated trophozoites. mp.= 
minute pore, probably contracted pore of entrance. .—nucleus of egg. 
ne.=nucleolus. np.=nucleus of parasite. o.=ovum. op. =opening,. 
p.=parasite. p! and p*.=associates. pr.—protoplasmic process. sp. = 
space left by parasite. sv.—perivitelline layer. ¢.—‘ tail’ end of tropho- 
zoite th.=threadlike structures in outer zone of egg. v.=vitelline 
membrane 
