452 MR. PERCY I. LATHY ON [Apr. 10, 



EXPLANATION OF PLATE XXXIII. 



Fig. 1. Transverse section of Lead of Trout embryo with superaumerary eye. 



L. Lens of supernumerarj' eye. Tr. Trabeculae cranii displaced towards 



S.. Retina „ „ ^ left. 



Jt.O. Right normal eye. j P-L. Palato-quadi-ate bar on left side; 



N. Right optic nerve receiving fibres ! the right bar is absent. 



from retina of supernnmerary eye. S.o. Supra-orbital bar. 



0. Central cavity of brain with two deep Au. Anterior corner of auditory capsular 



grooves in its floor, each of which cartilage. 



leads downwards into an infun- 



dibulum and a hypophysis. 



Fig. 2. Horizontal section of head of Trout embryo with supernumerary eye. 



i. Lens belonging to the left (aborted) j O. Functional left eye. 



twin head. CL. Functional cerebral lobes. 



CZi'. Cerebral lobes belonging to ditto. { CO. Cavity of optic lobes. 



Zrd V. 3rd ventricle belonging to ditto. : OL. Optic lobes. 



C. Cranial cartilages belonging to , Au. Auditory cartilage, 

 ditto. ' 



Fig. 3. Transverse section of the atrophied single head described above. 



L. The larger lens surrounded by \ U . The smaller hourglass-shaped lens, 



muscle-fibres, M. j P. Pineal body. 



CTi. Cerebral lobes. j T. Tegminal cartilage. 



Fig. 4. Transverse section through body of Trout embryo showing local deficiency of 

 the notochord. 



Sp.c. Spinal cord. Ao. Dorsal aorta. 



iV.c. ir.c. Neural and hiemal arch carti- ; (Es. ffisophagus. 



lages fused together. i Be. Body-cavity. 

 M^,M.^,M^. Divisions of the muscle- j 



masses. 



5. On Three New Forms o£ Butterfly of the Genus Heliconius. 

 By Percy I. Lathy, F.Z.S., F.E.S. 



[Received April 10, 1906.] 



(Plate XXXIY.) 



Heliconius pasithoe Cram., fulvescens, var. n. (Plate 

 XXXIY. fig. 1.) 



2 . Upper side. Fore wing black, with white markings as in 

 typical pasithoe Cram., but the ai'ea between discal white markings 

 and base chiefly fulvous. Hind wing black, with a long, narrow, 

 fulvous fascia below subcostal nervure, two obscure whitish spots 

 near apex. 



Under side. Fore wing similar to upper side, but fulvous 

 markings paler and discal Avhite markings slightly tinged with 

 yellow. Hind wing similar to typical pasithoe Avith exception of 

 following fulvous markings : a streak along costa as above but 

 slightly wider and paler, and a short, wide fascia from anal angle. 

 Antennje fulvous with basal half black. 



Rab. Demerara. Coll. H. J. Adams. 



One example of this remarkable form was obtained. I am 



