See also Sörensen, Journ. Anat. and Phys. xxix. 1895, p. 399; and Bridge, Journ. Linn. Soc. xxvii. 1900, p. 531.
Bridge and Haddon, op. cit. p. 261.
Id. Proc. Roy. Soc. lii. 1892, p. 139.
Kupffer, Stud. vergl. Entwickl. d. Kopfes d. Kraniaten, iii. 1895, p. 6.
In Bdellostoma the olfactory organ arises as a pair of outgrowths from the pituitary involution (Bashford Dean, Kupffer's Festschrift, Jena, 1899, p. 269).