TABLE I. MATURITY STAGES OF THE GOXADS
A. Examination under the binocular dissecting microscope, x 100. 13. Examination of sections.
Ovaries
Testes
Stage 0
A. Gonads not visible ; in transparent species primordial gonocytes
B. Primordial gonocytos.
can be seen.
Stage I
A. Gonads little developed, resembling a small mass, slightly
elongated, made of spherical cells.
B. Oogonia in multiplication. First ooeytes of first order in their
first period of growth. Some oocytes are a t beginning of second stage.
Synaptic stages in nucleus. Cytoplasm rather scarce but easily
stainable. Perinuclear granulations present. Seminal pouch and
crescent not yet formed.
Stage I1
A. Small but easily recognizable oocytes.
B. Oocytes in their second period of growth ; some may also be at
beginning of third period. Granulations around nucleus more numerous
than in former stage. Lampbrush chromosomes. Strongly stainable
cytoplasm. Oocytes in their second period of growth enter into contact
with seminal pouch by means of fecundation cells.
A. Gonads not visible. In transparent specics
B. Primordial gonocytes.
primordial gonocytes can be seen.
A. Testes visible though very small. There a.re
B. Spermatogonia in multiplication.
no male germ cells free in caudal coelom.
A. First germ elements free in caudal coelom.
B. Spermatogonia in multiplication. Small
masses of first and second order spermatoeytes free
in caudal coelom.