PLATE 1 
EXPLANATION OF FIGURES 
1 to 4. Spermatogonial complexes of Brachystola magna showing division of 
entire complex into two groups; one containing six smaller chromosomes, the other 
seventeen larger ones. Figure 2 does not contain all of the larger chromosomes 
but shows the accessory, x, in recognizable form. Of the smaller group the prob- 
able pairs are designated a, b, and c, respectively. One of those marked ¢ is 
obviously larger than any of the other five. 
5to6- Spermatogonial complexes of Arphia simplex. Two groups with regard 
to size are again evident with the difference that there are four smaller and 
nineteen larger chromosomes. Three members of smaller group are practically 
identical in size; the fourth, a, is smaller. 
7 Apical cell of Arphia simplex. Persistent chromatin vesicle k associated 
with flocculent mass of chromatin. 
8 Nucleus from one of the cells surrounding apical cell, containing two per- 
sistent chromatin vesicles k, k with their associated chromatin masses. 
9 Spermatogonial telophase of Arphia simplex showing vesicles k, k and asso- 
ciated chromatin threads. 
10 Spermatogonial prophase Arphia simplex. One end of associated chro- 
matin thread longer than the other. 
11 Spermatogonial spireme, Arphia simplex, c, telosynaptic union of unequal 
pair; x, accessory; p, polar granules. 
12 Early growth spireme, Arphia simplex. Position of persistent chromatin 
vesicle, k, on loop and relation of this loop to accessory, x, typical. 
13 Same as above at aslightly later period as shown by splitting of threads. 
Chromatin in vesicles k, k, k forming definite chromatin bodies. 
14 Fragment of nucleus, Arphia simplex. Chromatin bodies & still densely 
staining, associated thread thinner than ordinary threads. 
15 Very slightly later stage, Arphia simplex. Bodies k, k less densely stain- 
ing. 
16 Stilllater stage, Arphia simplex. Vesicle k persisting though nearly color- 
less. Associated thread more dense than ordinary threads. 4 
17 Part of cell of Brachystola magna near end of bouquet stage; x, accessory 
with precocious tetrad attached. 
18 Part of cell Arphia simplex near end of growth period; x, accessory; c, un- 
equal precocious tetrad attached to accessory. 18 e, x and c, later stage. 
19 The same; early prophase; x, accessory; c, unequal precocious tetrad; b. 
fragment of another precocious tetrad. 
20 Late prophase of Brachystola magna. Homogeneous accessory and asso- 
ciated precocious tetrad showing tripartite feature and greater density than ordi- 
nary tetrads. 
21 Spermatid, Arphia simplex. The three condensed elements still intact; 
x, one chromatid of accessory; b, one chromatid of larger precocious tetrad; c, 
one of smaller chromatids of unequal tetrad. 
22 The same except c, one of larger chromatids of unequal tetrad. Note that 
oe a of either spermatid is about } that of the nucleus at end of growth 
period. 
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