PLATE 2 



EXPLANATION OP FIGURES 



9 Cross section of head of a unilaterally operated larva showing reduction 

 in the height of crista (ct) and in the size of the right telencephalon. X 100. 



10 Cross section 690 microns anterior to figure 9 showing bony plate connect- 

 ing maxilla and premaxilla, the caudal end of the naso-lacrymal duct, the tectum 

 and solum nasi and the ethmoid column. X 100. 



11 Cross section 410 microns anterior to figure 9 showing the left telencephalon 

 with its glomeruli and no sign of the right, the distal end of the naso-lacrymal 

 duct and on the operated side the much thickened trabecula. X 100. 



ABBREVIATIONS 



ap, anterior trabecular plate 



apm, ascending process of premaxilla 



hp, bony plate connecting premaxilla 



and maxilla 

 ct, crista trabeculae 

 ec, ethmoid column 

 m, maxilla 



nl, naso-lacrymal duct 



ns, nasal sac 



.sn, solum nasi 



t, trabecula 



tc, tectum nasi 



tel, telencephalon 



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