32 Gen. Sub. 
GENERAL SUBJECTS. 
Joliet, L. Etudes anatomiques et embryogeniques sur . le Pyrosoma 
giganteum, suivies de recherches sur la faune de Bryozoaires de Roscoff 
et do Menton. Paris : 8vo, 112 pp., 5 pis. 
A posthumous publication of papers, containing, inter alia, “Observa- 
tions sur la Blastogeneso et la Generation alternanto clioz los Salpos et 
los Pyrosomes,” pp. 97-102. 
Karsten, H. Parthenogenesis und Generationswechsel in Tier- und 
Pflanzenreiche. Berlin : 8vo, 53 pp., 9 figs. (sop. Abdr. aua “ Die 
Natur y ‘). 
®Kennel, J. von. Ueber Teilung und Knospung der Tiere. Dorpat : 
Festrede, 4to, 26 pp. 
°KlSClT, E. H. Zur Geschlechtsenstehung beim Menschen. Humboldt, 
vii, pp. 297-299. 
Lang, A. Ueber den Einfluss der festsitzenden Lebensweise auf die 
Tiere, und fiber den Ursprung der ungeschlechtlichen Fortpflanzung 
durch Teiiung und Knospung. Jeua : 8vo, 166 pp. 
An important discussion of the relation between sedentary habit and 
various modes of asexual reproduction. 
Le Conte, J. Significance of Se*. Letter to Science, xi, 275, pp. 229 
& 230. 
(1) Notos that in 1879 & 1880 ho had published a suggestion that 
sexual reproduction was a source of variation, “such mixing produces 
more plastic nature ” &c. [So Treviranus, even]. (2) Differs from Weis- 
maun as to virtual identity of the nuclear substance in spermatozoon and 
ovum. (3) Refers to passage in which he has forestalled Hatschek’s 
theory (q. v.). 
Lo Bianco, S. Notizie biologicho riguardanti specialmente il poriodo 
di maturity sessuale degli animali del Golfo di Napoli. MT. z. Stat. 
Neap, viii, pp. 385-440. 
A valuable compendium of facts on periods of sexual maturity. 
Lucas, A. H. S. On the production of Colour in Bird’s Eggs. Tr. R. 
Soc. Yict. xxiv, 1 (1887), pp. 52-60. 
Mantegazza, P. Anthropologisch-kulturhistorische Studien fiber die 
Geschlechtsvorhaltnisse des Menschen. 2 Aufl. (From the Italian.) 
Jena : 8vo, 1883, ix & 384 pp. 
Maupas, E. Recherches experimentales sur la multiplication des Infu- 
soires cilies. Arch. Z. exp^r. vi, 1, pp. 165-277, 4 pis. 
Rate of reproduction varies greatly in different forms, with quality 
and quantity of food, with alimentary adaptation, and temperature, but 
also with constitution. Conjugation does not strengthen or accelerate 
division; but without it the members of an insulated family degenerate, 
become old, die ; it is essential to the life of the species. Details of this 
senile degeneration. The immortality of the Protozoa is dismissed as fan- 
ciful. The sexual character of the micro-nucleus is emphasized. 
