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Fishery Bulletin 111(2) 
o 
30 40 50 60 70 80 90 110 
Fork length (cm) 
Figure 4 
Fork lengths of Tilefish ( Lopholatilus chamaele- 
onticeps) sampled in 2008 from (A) ports of the 
northeastern United States ( /? =5 1 10) and (B) 
trips on cooperating commercial Fishing vessels 
during June and July 2008. In panel B, plotted 
histograms are overlapping (not stacked) and 
depict the numbers of individuals examined by 
macroscopic characters only (gray), histological 
characters only (black), and both methods (di- 
agonal lines). 
vey, 1991). An information-theoretic approach was used 
to select among full and reduced models; the second- 
order Akaike’s information criterion (AIC c ) was used to 
account for sample sizes in all comparisons. 
Model selection began with evaluation of logit, pro- 
bit, and complementary log-log model fits to FL or age, 
and histological maturity data, by sex. The logit model 
was selected because it consistently had a lower or a 
tied score (<2 AAIC c value) compared with the score of 
the probit model and a much lower score than that of 
the complementary log-log model. 
The logit-link function was used for selection of full 
or reduced models (i.e., by sex [logit {mature) ~ FL + 
Sex + FL:Sex], method [macroscopic, histological], or 
year [1978, 1982, 2008]). Model results from 2008, as 
presented in Tables 2 and 3, are from analyses of in- 
dividuals with both size and age data. Additional fish 
were measured for FL only, but inclusion of these fish 
in the analyses did not substantially change any re- 
sults. Historic data were extracted from Grimes et al. 
(1988). Because FLs in Grimes et al. (1988: tables 3 
and 4) were pooled by 5-cm bins, when entering their 
data for analysis, we assigned FL values for each fish 
as a midpoint value. Grimes et al. (1988: tables 5 and 
6) reported older fish as a plus group (i.e., 15+); there- 
fore, we also grouped all fish >15 years old together as 
a plus group to be consistent between studies, but the 
use of this plus group did not alter any result. 
Results 
Gonad histology 
No seminiferous tissue was evident in any functioning 
females, but morphologically intersex males, occurring 
in 2 morphs, were observed (Fig. 5). In the first morph, 
a lumen was evident but seminiferous tissue arose di- 
rectly along the gonad wall and no oocytes were pres- 
ent (Fig. 5A). Males with a lumen were common, but 
their frequency was not quantified because many histo- 
logical sections were incomplete across the transverse 
plane and the lumen was relatively small and difficult 
to recognize in larger testes. The other morph of inter- 
sex males appeared as rare, isolated, primary growth 
oocytes interspersed in continuous seminiferous tissue 
(Fig. 5B). This morph was observed in 4 young fish, 
ages 3 or 5, and at least some of the embedded oocytes 
were visibly degrading. In other males, remnant gaps 
in seminiferous tissue were evident, indicating that 
isolated oocytes had been present but were now fully 
degraded (Fig. 5C). 
The immature testis was initially dominated by 
spermatogonia surrounded by connective tissue, with 
limited spermatogenesis in the form of spermatocytes 
and spermatids in crypts surrounded by germinal epi- 
thelia (Fig. 5C). As spermatogenesis proceeded, sper- 
matozoa were released into lobules lined with a discon- 
tinuous germinal epithelia (i.e., spermiation), signaling 
physiological maturity (Fig. 5D). 
The ovary of immature females was dominated by 
oocytes at a perinucleolar stage (Fig. 5E). In many 
females classified as immature, the appearance of or- 
ganelles (i.e., a Balbiani body) and early formation of 
cortical alveoli were common in the cytoplasm of the 
largest primary growth oocytes (Fig. 5F); we consid- 
ered these traits characteristic of a maturing state 
(rather than a mature one), where such individuals 
were only preparing to mature and would not spawn 
until the following year. Only a single individual had 
advanced cortical alveoli as the most advanced oocyte 
stage (Fig. 5G), and 2 other females had only begun 
