Johnston, Morphology of the Head. 273 



Strong. 



126. Review of Locy No. 86. Jottr. Comp. Neitr. and Psych., Vol. 14, 

 p. 281. 1904. 



Hoffmann. 



127. Zur Entwickelungsgeschichte des Selachier Kopfes. Anat. Anz., 

 Bd. 9, 638-653. 1S94. 



DESCRIPTION OF FIGURES. 



Abbreviations . 



I, 2, J, etc. — mesodermic somites of van Wijhe. 



i, ii, iii, etc.— neuromeres of Locy. 



A - praeoral entoderm connected with the origin of somite i and the anterior 

 head cavity. 



a-l. — area of the primitive neural plate which gave rise to the acustico-lateral 

 system. Hypothetical. 



au. V. — auditory vesicle placode. 



bi, b2, etc. — branchial clefts. 



Bi, B2, etc. — branchial apches. 



ch. — notochord. 



cil. ^.—ciliary ganglion. 



e. I — anterior epiphysis. 



e. 2 — posterior epiphysis. 



h. — hyomandibular cleft. 



H — hyoid ^rch. 



hab. — ganglion habenulae. 



h. I. — portion of common acustico-lateral placode in selachians which goes to 

 form the head lines. 



int. arc. — internal arcuate fibers from cutaneous centers. 



L — nerve of Locy (Fig. 10) and its center (Fig. 7). 



/. /. — portion of acustico-lateral placode which forms the lateral line. 



m. — mouth. 



M — mandibular arch. 



mes. — mesoderm. 



N. I, II, III, etc. — cranial nerves. 



N. olf. — nervus olfactorius. 



N.prof. — nervus ophthalmicus profundus. 



N. thai. — nervus thalamicus of Platt. 



op. V. — optic vesicle. 



s. — striatum. 



s. m. — somatic motor column. 



sp. m. — splanchnic motor column. 



sp. J'. —splanchnic sensory column. 



