ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 989 



Intermediate Host of Ascaris lumbricoides.* — Dr. 0. v. Linstow 

 finds that Julus guttulatus and the closely allied Pohjdesmus com- 

 planatus greedily eat eggs of Ascaris lumbricoides which have been 

 for a long time in water or damp earth ; eighteen hours after eating 

 them the eggshell was found to be dissolved in the intestine ; thence 

 the young make their way into the body-cavity. These myriopods 

 have the habit of rolling themselves up, and are no doubt often eaten 

 •with the produce of the fields. The whole process of development 

 remains to be worked out. 



Vitality of Smut-Anguillulae.t — M. G. Fennetier has repeated 

 the old observations of Baker, Needham, and Davaine, as to the 

 vitality of Anguillulse in smutty grains of corn. Since 1872 he has 

 kept dried smutty grains in his laboratory, and six or eight of these 

 have been experimented upon every year. The grains are put into 

 watchglasses, exposed under a bell-glass to damp air, and after some 

 days supplied with water. Till last year revivification of the larvee 

 always occurred, but with decreasing completeness; last year the 

 revivification was hardly demonstrable ; this year the results were 

 wholly negative. Fourteen years seems therefore to be about the 

 limit of the resistance to desiccation. 



Nervous System of Cestodes.J — Dr. J. Nicmiec has continued 

 his researches on the nervous system of Cesiodes, extending his 

 previous investigation of Tsenise to numerous other forms. 



1. The nervous system of Ligula consists of two longitudinal 

 strands, traversing the entire body, and united at the apes of the head 

 by means of large ganglion-cells, which form the central organ. 

 From the latter ten to twelve nerve-filaments proceed, at first united 

 here and there with the main strands, but extending along the dorsal 

 and ventral surfaces till they gradually disappear in the anterior 

 third of the body. 



2. The nervous system of Scliistoceplialus dimorphus resembles the 

 above. Two lateral ganglia are united by a median, and by two — 

 dorsal and ventral — commissures. They give origin to eighteen 

 twigs, of which the two lateral, which are the strongest, extend 

 throughout the entire chain, while the dorsal and ventral filaments 

 are traceable as far as the sixth joint or thereabouts. 



3. The nervous centre of the Bothriocephali lies near the apex of 

 the scolex. Histologically it resembles Ligula. Besides the main 

 strands eight delicate nerves arise, which are here and there united 

 with one another and with the main strands by means of slender' 

 commissures. They disappear at the beginning of the neck region. 

 Small branches run forward to the very apex of the head. 



4. The complex structure of the nervous system in the Tsenise 

 scolex is a modification induced by the musculature of the suckers 

 and hooks, (a) The nerve-ring is an adaptation of the head-nerves to 

 the circular course of the hook-muscles. It is peculiar to Tsenise, 



* Zool. Anzeig., ix. (1886) pp. 525-8. 



t Comptes Rendus, ciii. (188ti) pp. 284-6. 



t Arbeit. Zool. Inst. Univ. Wien (Glaus), vii. (1880) pp. 1-C.O (2 pis.). 



