BIOLOGY. 305 



Date or secondary germ. From the first are developed the most 

 essential tissues, as the nervous, muscular, and epithelial ; from 

 the second the skeletal and nutrient structures, as cartilage, 

 bone, connective tissues, and the vascular system. The develop- 

 ment of these two portions may be distinguished in the early 

 embryo, but afterwtirds they grow into each other, producing a 

 complex interlacement of ))arts. The development of the second- 

 ary germ is very much affected by mechanical conditions. The 

 perivascular lymph-spaces of the brain, discovered by him, are 

 shown to arise from the intrusion of blood-vessels formed b}' the 

 secondary germ into spaces excavated in the primary germ. 



The Glass-rope Sponge. — Prof. Loven is doubtless right in sup- 

 posing, from the study of a sponge which he called Hyalonema 

 horecde (but which does not belong in this genus), that the long 

 tuft of glassy fibres constituting the so-called axis is the pedicle 

 by which it is fixed in the sea-bottom, and that the sponge grows 

 on the top of this. This is confirmed by Profs. Wright and 

 Tiiompson, and Dr. Carpenter. Dr. Wright thinks Max Schultze 

 correct as to the parasitic nature of the coral which sometimes 

 encrusts the axis of Hyalonema, which is a true sponge. Dr. 

 Gray, however, retains his opinion that the axis is the work of the 

 coral, and that the sponge on the end of it is parasitic. — Quart. 

 Journal of Science, Jan., 1869. 



Singular Mode of Reproduction in a FisJi. — The species observed 

 was from China. When the season for laying the eggs arrives, 

 the male projects from the mouth little globules of air, which rise 

 to the surfLice, but do not burst, probably consolidated by mucus 

 as they come out. In this way he forms upon tlie water a roof of 

 froth, often a centimetre thick ; this is the receptacle for the eggs, 

 in which the hatching is completed. Then the sexes come together, 

 the male forming a complete ring in wiiich the female is pressed, — 

 an approach to the sexual congress of the higher annuals. The eggs 

 are fecundated as they leave the female, and the male collects the 

 scattered masses and arranges them in proper thickness under 

 the roof of foam ; he watches them, taking no food, from 62 to 

 65 hours, when the young appear; he keeps these within the 

 protecting roof until they can provide for themselves, bringing 

 back any wanderers in his mouth. — Comptes Bendus, Aug. 16, 

 1869. 



Extinct Reptiles. — From the investigations of Mr. E. D. Cope 

 ("Trans, of Amer. Phil. Society," Aug., 1869), it is stated, 1. 

 That the Dinosauria present a graduated series of approxinia- 

 tions to the birds, and possess some peculiarities in common with 

 that class, standing between it and the Crocodilia; 2. That ser- 

 pents exist in the eocene formations of this country ; 3. That the 

 Chehjdra type was greatly developed during the American creta- 

 ceous, and that all the supposed marine turtles described from it 

 are really of the first-named group ; and, 4. That the reptiles of the 

 American triassic arc of the Belodon type. 



Reproduction hy Larval Batracldans. — According to M. Jullien, 

 ♦'Comptes Rendus," April 19, 1869, the Lissotriton punctatus may 

 reproduce its specie's while in the tadpole state. He found in the 



26* 



