September 23, 1898.] 



SCIENCE. 



401 



is the most primitive known species of the 

 genus. 



In the cranial osteology ofDininchthys inter- 

 medius the ' parietal ' and ' frontal ' elements 

 of Newberry and other authors, declared 

 not to exist, the area assigned to them be- 

 ing covered by the centrals, as in D. pustu- 

 losus, and uniformly throughout the family. 

 Identification of the side plates of the body, 

 heretofore considered missing. The upper 

 or transverse arm of the ' clavicular ' is 

 homologous with the anterior lateral of 

 Coccosteus, and the inner branch of the bi- 

 furcated arm with the interlateral of the 

 same genus. Outer branch of the bifur- 

 cated arm has articulated to its distal end 

 a warped plate, supposed to represent a 

 modified branchiostegal apparatus. The 

 term ' clavicular ' is thus a misnomer, since 

 the element has nothing to do with a 

 shoulder-girdle, and there is no evidence 

 that such a structure was present in the 

 Dinichthyids. 



The orientation of the clavicular was de- 

 scribed and illustrated by diagrams. The 

 osteology of Titanichthys agassiszii was also 

 described and illustrated by diagrams. 



Transformation of the Brook Lamprey (Lam- 

 petra wilderi), and Parasitism among Lam- 

 preys. By Professor Simon Henry Gage. 

 The transformation of all lampreys is 

 similar, as far as known. The egg develops 

 into a larva comparable to a tadpole, and 

 this transforms into an adult. Up to the 

 present the larvae of the sea, lake and 

 brook lampreys have not been distinguished. 

 At transformation the sea and lake lam- 

 preys are about 150 mm. long, while adults 

 average 700 and 350 mm. respectively. 

 The transformation of the lake lamprey re- 

 quires 20-30 days until adult form is as- 

 sumed, but metamorphosis is only begun in 

 this time, and the animal stays under the 

 sand, like a larva, for about 4 months before 

 emerging for a free predatory life. 



The brook lamprey attains full size dur- 

 ing larval life, and remains under sand 

 some 7 months ; it then emerges, builds nest, 

 lays eggs and dies. In the lake lamprey 

 {Petromyzon marinus unicolor), from Cayuga 

 Lake, no food, except blood, has been found 

 in the enteron. As the brook lamprey has 

 the same armature of teeth and rasping 

 tongue as lake and sea lampreys it has been 

 considered as also parasitic, but this is a 

 mistake, as shown by experiments in 

 aquaria. The suctorial mouth is used in 

 all lampreys for nest building and mating ; 

 the question arises : was the buccal arma- 

 ture developed for this purpose or for a 

 parasitic life? 



Hybernation, Transformation and Growth of the 



Common Toad(Bufo lentiginosus americanus) . 



By Professor Simon Henry Gage. 



In literature it is stated that the toad 

 hybernates under leaves, logs, etc. From 

 observation it is believed hybernation oc- 

 curs only in the ground, rather dry and not 

 liable to be frozen. After emerging in 

 spring, if a cold snap occurs, they seek 

 shelter of leaves, etc. In burying itself the 

 toad backs in, the hind legs and caudal end 

 of body being used for digging, and fore- 

 legs for pushing backward. No sign of the 

 hole is left. 



In a freezing atmosphere the temperature 

 of the toad was f to IJ degrees Centigrade 

 higher than surrounding medium. Toads 

 found under frozen leaves were able to 

 crawl. In one case the legs and skin were 

 frozen solid, but not the internal organs; 

 the toad recovered. When frozen solid the 

 toad never recovered. 



At Ithaca ovulating extends from the 

 middle of April to the middle of June. Eggs 

 are normally laid in a double string, one 

 from each oviduct ; 500-5,000 or more are 

 laid at one time. Eggs hatch in about 4 days. 

 Growth of tadpole is attained in about 40- 

 60 days. After hind legs are well developed 



