ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 289 



whereas in the ciliated cells the nuclei are near the base which terminates 

 in a caudal prolongation. Between these caudal processes of the ciliated 

 cells there is a layer of round cells, resting on a thin basement membrane. 

 An area of ciliated cuboidal cells occurs at the margins of the maculge. 



Eye of Blanius cinereus.* — A. Menacho has made a detailed study 

 of the eye of this Ampliisbfenid lizard. The eye is deeply hidden. 

 There is a conjunctival sac, lined by a single layer of cylindrical 

 epithelium. It receives the secretion of the orbital glands. The 

 Harderian gland is greatly developed. There are no muscles moving 

 the eye. The sclerotic has an incomplete cartilaginous ring. There is 

 no true cornea, nor anterior chamber, nor ciliary muscles. The lens 

 shows much degeneration ; there is no cellular structure or only a few 

 nuclei. The retina is very embryonic, showing, like the sclerotic, 

 arrested development. There is no vitreous humour. There is no 

 confirmation of Eigenmann's view that the most active parts are the 

 first to degenerate ; thus the lens and the vitreous humour cannot be 

 called active. 



Course of Vagus Branches on the Stomach. t — Einer Perman has 

 studied the minute details of the branching of the vagus on the wall of 

 the stomach in man. Between the ramification and the main stem 

 there is no such plexus as is described under the names of anterior and 

 posterior gastric plexus. Each vagus nerve gives off in the cardiac 

 region a number of branches, of which five to seven pass directly into 

 the longitudinal part of the stomach, while a very strong branch passes 

 through the omentum minus to the transverse part. The further 

 branching is carefully described. There is no sub-serous ganglion- 

 plexus. 



Structure of Fish-scales.:}: — N. Rosen distinguishes in the making 

 of scales two kinds of elements — namely, teeth and sclerosed plates in the 

 corium. The plate consists of an outer, homogeneous layer, due to the 

 outer layer of the corium, and an inner, fibrillar layer, due to the inner 

 layer of the corium. 



Three chief types of scales may be distinguished. 1. The scale may 

 consist of a tooth only, as is the case in the fossil Coelolepidje, and may 

 perhaps be the case in some Selachians. 2. The scale may consist of a 

 plate (with an outer homogeneous and an inner fibrillar layer) which 

 bears a tooth or several teeth. The plate may be penetrated by a 

 system of canals and cavities, in which blood-vessels and nerves extend 

 to the outer corium layer and the pulp of the tooth portion. This type 

 is represented by the placoid scales of Selachians (with one tooth on 

 each slightly developed plate), and by the Lepidosteiis scales (with 

 several, usually small, sometimes deciduous teeth and with a well- 

 developed plate). 3. The scale may consist of a plate as before, but 



* Trabajos Mus. Nacional Ciencias Naturales Madrid. Serie Zoologica, No. 21 

 (1915) pp. 1-48 (6 pis.). 



t Arkiv f. Zool., i. (1916) No. 11, pp. 1-37 (9 figs.). 



X Arkiv f. Zool., x. (1916) No. 7, pp. 1-36 (1 pi. and 18 figs.j. 



