Phthinobranchii ae 
delicately at his readiness and ability to defend her children 
against every enemy, vows unfailing fidelity, and in lover fashion 
promises as much in a few minutes as would take a lifetime to 
fulfill. Of course she listens to his suit; personal beauty, 
indomitable courage, backed by the substantial recommendations 
of a house ready built and fitted for immediate occupation, 
are gifts not to be lightly regarded. 
“Throwing herself on her side the captive lady shows her 
appreciation, and by sundry queer contortions declares herself 
his true and devoted spouse. Then the twain return to the 
nest, into which the female at once betakes herself and therein 
deposits her eggs, emerging, when the operation is completed, 
by the opposite hole. During the time she is in the nest (about 
six minutes) the male swims round and round, butts and rubs 
his nose against it, and altogether appears to be in a state of 
defiant excitement. On the female leaving, he immediately 
enters, deposits the milt on the eggs, taking his departure through 
the back door. So far his conduct is strictly pure; but I 
am afraid morality in stickleback society is of rather a lax 
order. No sooner has this lady, his first love, taken her depart- 
ure, than he at once seeks another, introduces her as he did 
the first, and so on, wife after wife, until the nest is filled with 
eggs, layer upon layer, milt being carefully deposited betwixt 
each stratum of ova. As it is necessary there should be two 
holes, by which ingress and egress can be readily accomplished, 
so it is equally essential in another point of view. To fertilize 
fish-eggs, running water is the first necessity; and, as the holes 
are invariably placed in the direction of the current, a steady 
stream of water is thus directed over them.” 
To the genus Gasterosteus the largest species belong, those 
having three dorsal spines, and the body typically fully covered 
with bony plates. Gasterosteus aculeatus inhabits both shores of 
the Atlantic and the scarcely different Gasterosteus cataphractus 
swarms in the inlets from southern California to Alaska, Siberia, 
and northern Japan. Half-naked forms have been called by 
various names and one entirely naked in streams of southern 
California is named Gasterosteus williamsont. Its traits are, 
however, clearly related to its life in fresh waters. 
In Pygosteus pungitius, a type of almost equally wide range, 
