190 ~=6© Papers from the Marine Biological Laboratory at Tortugas. 
Rhynchobothrium speciosum, from cyst in Mycteroperca bonaci. 
78. Cyst, sketch from life; actual length 22 mm. 
79. Same, flattened so as to show blastocyst. cy, cyst; /, larva; pg, brown pigment sur- 
rounding b/, the blastocyst. 
Rhynchobothrium sp., from Dasyatis say. 
80. Entire specimen, balsam; actual length 090 mm. | 
81. View of proboscis at base, partly diagrammatic; diameter, exclusive of hooks, 
0.017 mm. ; : 
82. Another view of proboscis near base; diameter, exclusive of hooks, 0.014 mm., 
length of longest hooks 0.007 mm. 
Rhynchobothrium sp., from Clupanodon pseudohispanicus. 
83. Head and neck, balsam; actual diameter of head 0.22 mm. 
84. View of proboscis near base; diameter, exclusive of hooks, 0.017 mm. 
85, 86. Other views of proboscis. 
87. Characteristic appearance of margins of proboscis; length of longest hooks 
0.010 mm, 
