Journal of morphology . al ganglia stillremain as in the preceding stage, while the other ganglia arebeing drawn apart by the stretching of the embryo, so as toshow their short connectives. In Fig. C, the suboesophagealand last abdominal ganglia are established as two fused number of ganglia comprising each of these masses maystill be easily determined by counting the commissures. Itwill be noticed that in this stage the first abdominal is closelyapproximated to the metathoracic ganglion and that the secondand third abdominal also lie close together. Between theother ganglia the con
Journal of morphology . al ganglia stillremain as in the preceding stage, while the other ganglia arebeing drawn apart by the stretching of the embryo, so as toshow their short connectives. In Fig. C, the suboesophagealand last abdominal ganglia are established as two fused number of ganglia comprising each of these masses maystill be easily determined by counting the commissures. Itwill be noticed that in this stage the first abdominal is closelyapproximated to the metathoracic ganglion and that the secondand third abdominal also lie close together. Between theother ganglia the connectives have lengthened. In the laterstage represented in Fig. D, the connectives are still longer;the first abdominal ganglion has fused with the metathoracic,and th© second and third abdominal form a single mass. 92 WHEELER. [Vol. VIII. These fusions become more intimate as the time for hatchingapproaches, so that the ventral cord finally consists of only-ten ganglia instead of sixteen, the original number. -VX?,^C*. i(>.cvos;i
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