EVOLUTION. 
Gen . Sub. 81 
Coloration of Mammals : stripes supposed to be derived from fusion 
of spots in lines, and spots supposed to correspond to (hypothetical) 
armour-plates in ancestral forms. The evolution of markings supposed 
to be primarily independent of utility ; Bonavia (52). — So - called 
attractive coloration in animals ; Reeker (565). 
Seasonal Dimorphism : renewal of experiments. Distinction between 
direct seasonal dimorphism, referable to the direct action of variable 
environment, and adaptive seasonal dimorphism, the outcome of a process 
of selection. An example of the former is Chrysophanus plilceas , of the 
latter, the caterpillar of Lycama pseudargiolus, and perhaps Vanessa prorsa- 
levana. On the forms which illustrate adaptive dimorphism, the changes 
of temperature act only as “ Auslosungsreize.” In P. napi both kinds are 
probably mixed ; Weismann (739). — Seasonal dimorphism of Bhopalo- 
cera ; Barker (22). 
Origin of larval markings and armature of Bombycine larvae ; 
Packard (507). 
Albinism ; Roth (593) : Causes and transmission of ; Ha acre (269). 
Colour variation, see p. 77. 
Ergatogynous forms of ants. Theory that the ovum includes a double 
Anlage (of queen and worker), this responds differently to developmental 
stimuli, such as food ; W asm ann (733). 
Forel’s observation of intermediate forms between fertile females and 
workers in one nest but not in adjacent nests : facts favour Weismann’s 
view that the differences are due to germinal variation ; Wagner (722). 
Origin and evolution of web-spinning : First a case for eggs, then a 
tubo to conceal the mothor, thon ovolution along two main linos — tho 
trap-door nest and the snare-net ; Pocock (530). 
The origin of species among flat-fishes ; Cunningham (127). 
Heterocercy of bottom-fishes and pseudo-heterocercy of surface-fishes 
interpreted as adaptations to sculling in (dangerous) proximity to the 
limits of the water ; Ahlborn (2). 
Darwinism illustrated in reference to the birds of New Zealand ; 
Buller (89). 
Adaptation of insects to new conditions ; Behr (32). 
The case of the cuckoo; Rey (574). 
Electric organ of skate ; Purvis (541) \cf. Fritsch (217)]. 
Migration, problem of ; Gatke (223). — Influence of light on the 
periodical depth-migrations of pelagic animals ; Loeb (404). 
Mimicry in insects ; Scudder (643) ; see also xm, Insecta , p. 87. 
Problems in connection with instincts of social insects ; Hartog (287). 
The origin of food of marine animals — the micro-organisms of the 
surface ; Brooks (76). 
Natural history of aquatic insects ; Miall (446). 
For associations of animals, parasites and similar subjects, see 4, 
p. 61. 
