September 21, 1S83.] 



SCIENCE. 



411 



water, — in sixty to one hundred and sixty fathoms, 

 — which has a more soutliern fauna than the colder 

 waters either side. Professor Verrill has suggested 

 that there was a great destruction of life in this belt 

 in the winter of IS.'^l-8'2, caused by a severe storm 

 agitating the bottom-water, and forcing outward the 

 cold water that occupies the great area of shallow 

 sea along the coast, thus causing a sudden lowering 

 of the temperature along the warm belt. 



Among tlie forms described are two new genera of 

 Galalheidio, in one of which there are no appendages 

 on any of the first tive abdominal somites of the 

 adult male, liul the nu)st interesting forms are two 

 genera of lR'rinit-cral)s, — Parap:igurus and Sympa- 

 gurus, — in which the brancliiae present types of 

 structure intermediate between the phyllobranchiae 

 of ordinary paguroids, and the trichobr.anchiae of the 

 Astacidae, etc. — (Proc. nat. mxui., \i., June, 1883.) 

 s. I. s. [257 



VERTEBRATES. 



Development of muscle fibres and their union 

 ■with nerves. — Altliough \ ery numerous researches 

 liave been made on the dilTerentiation of striped 

 muscles, and on the termination of their motor nerve- 

 fibres, yet the multifarious observations h.ave often 

 been too incomplete to lead to any but conflicting 

 and unsatisfactory theories. An important contribu- 

 tion toward reducing this unfortvinate and excessive 

 confusion to order is made by L. Bremer, who has 

 studied the post-embryonic changes in lizards, frogs, 

 and mice. The nucleus of tlie muscle-fibre, together 

 with the pi-otoplasm surrounding it, constitutes the 

 so-called muscle-corpuscle; the corpuscle is much 

 more prominent in young than in old muscles, for 

 its protoplasm is gradually differentiated into muscu- 

 lar substance; a small number of corpuscles enters 

 into the formation of each fibre; the substance of the 

 muscle forms a network, which was first partially 

 recognized by Heilzmann ( Wien. ■•siUunr/nber. xvii. 

 abth. 3, 1873) ; the meshes of this network appear 

 polygonal in transverse, rectangular in longitudinal 

 sections; the network is a modification of the proto- 

 ])lasmatic network of the corpuscles, and is so arranged 

 that there are alternating rows, both transverse and 

 longitudinal, of fine knots and large knots (correspond- 

 ing to the fine ami broad striae); the fine knots are 

 connected by fine threads, and the large knots by 

 coarse threads; hence there is a fine and a coarse net. 



The post-embryonic multiplication of fibres takes 

 place by means of the structures described by Margo 

 ( Wien. sitzungnber. xxxvi. 2211) under the name of 

 'sarcoplasteii ;' there are lines or chains of musclo- 

 corpuscles, united by the protoplasm net, and derived 

 by proliferation from the corpuscles of the original 

 fibres; the sarcoplast gradually separates from the 

 parent fibre, undergoing muscular differentiation 

 meanwhile, ami also becoming contiected with the 

 nerve. The growth of the fibre is initiated by a 

 multiplication of the corpuscles; the sarcolemma is 

 not present at first, but apiiears later, being probably 

 formed by the fused cell membranes of the corpus- 

 cles, to which appears to be added a coat of coiniec- 

 tjve tissue, and also around the motor plate between 



the two sarcolemmic coats, an extension of Henle's 

 sheath of the nerve. 



The motor nerve plates are formed as follows:. 

 When the sarcoplast begins to change to muscle, the 

 nerve grows towards it until the two meet and unite. 

 In lizards only a single nerve-fibre, in the frog and 

 mouse several together, thus approach the future 

 muscle. At the jioint of contact, the muscle-cor- 

 puscles change, so that an accumulation of proto- 

 plasm and a proliferation of nuclei occur there. 

 These accumulations were first described by Kiihne 

 under the name of ' niuskelspindeln ' (Virchow's 

 arch., 1863, 116), and are mentioned by many subse- 

 quent writers: Bremer now shows that they are 

 young 'end-plates.' Into these the ramifications of 

 the nerve penetrate, after the medullary sheath has 

 been lost. The details of the process, of course, vary 

 in different animals, as do also thi^ final forms of the 

 motor plates. 



Besides the motor terminations, there are others, 

 which the author believes to be probably those of the 

 sensory nerves. The fibres running to them are 

 either small and medulUitc'd, or naked and end in 

 ramifications upon the muscle, without any conspic- 

 uous collection of nuclei and protoplasm at the place 

 of junction. The smaller nerve endings occur on 

 the same fibres with the motor plates, and probably 

 both exist on every fibre. The smaller endings, 

 Bremer designates as 'enddolden' in contradistinc- 

 tion to the 'endplatten.' (Sach's paper on the sensory 

 nerves of muscles is not cited by Bremer.) 



Hensen has advanced the view that the connection 

 between the nerves and the peripheral cells exists 

 from the first in the embryo, and that, as the cells 

 divide, so do the nerves. Bremer's observations 

 show that with muscles this is not the case. More- 

 over, Kleinenberg's theory of the evolution of muscle 

 and nerve must be at least modified, if not .set aside. 

 (That the union of the nerve-filament with the pe- 

 ripheral organ is secondary, is shown also by His. 

 Science, i. 956.) — (Arch. mikr. anat. xxii. 318.) 

 c. s. Ji. [258 



ANTHROPOLOGY. 



Folk-lore in the Paujb.— Mrs. F. A. Steel is 

 collecling the folk-stories among the natives in 

 the Panjab. No. 18 is a charming shepherd-tale 

 common among the cattle-drover's children in the 

 forests of the Gujranwala. It is about Little Ankle- 

 Bone. Once upon a time a little shepherd was eaten 

 by a wolf, that hung the ankle-bone of his victim 

 to a tree. Some robbers, dividing their spoil, were 

 startled by the falling of the bone, which became a 

 little lad, and did many wonderful things, taming 

 all the beasts of the field, and fowls of the air. He 

 changes a pond into milk, by the side, of which he 

 sits under an oak-tree, playing his shepherd's pipe, 

 while all the animals come to listen, and to drink out 

 of his marble basins. The series will be continued. 

 — {Imlian antiquary, xii. 10.5.) j. w. p. [259 



Lorillard City. — .\flcr his researches at Chichen- 

 Itza, M. Charnay made an e.xcursion into the country 

 of the Lacandones, — a fierce, indomitable tribe, of 

 whom it is most desirable to have more information. 



