ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 301 



until after the middle of November. The eggs are seldom eaten by other 

 animals. Great numbers of tadpoles are destroyed by insects and insect 

 larvae. Birds, fishes, and reptiles feed upon tadpoles. A large per- 

 centage of the eggs and larvae are killed by the lowering of the water. 

 Toads are destroyed, chiefly, by all classes of Vertebrates, by drought and 

 winter, and by the sewer systems of towns. 



Transformation of Palatal Region in Axolotl.* — P. Wintrebert 

 finds that the larval vomer and palatine disappear during the metamor- 

 phosis. They undergo progressive decalcification. The so-called ptery- 

 goid bone, the " queue pterygoidienne " of the palatine, does not exhibit 

 more than a partial involution. There is an autonomous formation of a 

 new vomer, in which the palatine does not share. A new perichondria! 

 ossification around the cartilaginous pterygoid is added to the partially 

 retrogressive ossified part mentioned above. 



Palatine and Pterygoid in Axolotl.t — P. Wintrebert finds that in 

 a normal axolotl these two bones form one piece. An axolotl in bad 

 condition absorbs more or less of its vomerine-palatal-pterygoid appa- 

 ratus according to its degree of emaciation. A branchiate " Amblystoma " 

 shows no palatine, a pterygoid as in the adult, and a well-ossified but 

 incomplete vomer, 



Rostral Teeth of Pristis.i — H. Engel finds that these teeth are in 

 structure and development allied to placoid scales. There is an epider- 

 mic enamel organ and a mesodermic tooth-germ. The primordium 

 sinks into the mesoderm. There is pulp and a vascular reticulum in the 

 young stages and the blood-vessels persist. The superficial layers of 

 the point are vitrodentine and dentine. These are soon worn off and 

 vasodentine is left. There is no replacement. 



Suctorial Disc of EcheneisJ — Reinhard Honv srives an account of 

 this extraordinary structure, discussing its musculature and sensory 

 apparatus, and its innervation from the first five spinal nerves and a 

 branch of the vagus. He goes into the evidence, showing that the 

 organ has not arisen in its present position, but has passed from the 

 trunk on to the head, apparently as a transformation of the anterior 

 dorsal fin. 



Notes from Millport Biological Station. ||— R. Elmhirst notes that 

 the hermit-crab which is usually associated with the sponge Suberites 

 domuncula is Eupagurus pubescens (Kroyer), just as E. prideauxii is 

 always found associated with the cloaklet anemone Adamsia palliata. 

 But in three cases out of several thousands E. bernhardus was found 

 with the sponge. Elmhirst has also some notes on the moulting and 

 regeneration of Galathea strigosa, and on the lobster's aquarium habit 

 of heaping up pebbles. He cites a case of a lobster burying its cast 

 cuticle. The " spout-fish " (Solm) withdraws suddenly into its hole. 



* C.R. Soc. Biol. Paris, Ixviii. (1910) pp. 178-80. t Tom. cit.. pp. 419-20. 



t Zool. Jahrb., xxix. (1909) pp. 51-100 (4 pis. aud 2 figs.). 

 § Tom. cit., pp. 101-38 (4 pis. and 1 fig.). 

 Zoologist (Feb. 1910) 3 pp. 



