1. I explained about the influence given to the first larva of Atypus karschi by Agelena opulenta in the case of formation of their winter-colony.
2. There are four cases which are called the influences given by Agelena opuknta.
a. The formation of the Atypus karschi's colony do not progress easily.
b. It takes too much time to complete the colony.
c. It is difficult for them to make the fixed colony.
d. They make the fixed colony at the place of low value.
3. Every colony never mix one another.
4. Atypus karschi in the mixed group is weak against the Agelena opulenta in the closed ecosystem such as the petridishes, so their colonies are generally small and unstable, and the growth rate is very small. We saw this in Morishita's Iδ-index curves.

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The present gynandromorphic spider was collected by one of the authors, T. Arita, at Inoko, Tottori City, on May 12, 1961.
Seen from above the coloration of the left half of the carapace and abdomen is that of a female whereas the right half is distinctly that of a male. The left chelicera and palp are typical for a female, while the right ones are like those in a male. The left palp is slender, and the tarsus of the right palp swollen as in a male, but the structure of its genital bulb is not fully developed. The left legs are slightly shorter than the right ones, ix the left are feminine and the right masculine. The spination on the left legs is as in a female, and that on the right as in a male. The abdomen is strongly asymmetrical, with the left side larger than the right. The epigynum is like that of a normal female, although being more or less different in shape and the left(seen from below)chitin cap is wanting. Spinnerets are normal as in a female. As a whole, this individual seems to be an intersexual mosaic gynandromorph with a preponderance of femaleness.

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1. Neoscona scylloides BOESENBERG et STRAND
The spider was collected by Mr. Y. Suganami at Mt. Tsuchidake on August 21, 1965. The general appearance is that of an adult male: chelicerae, carapace, spination of legs and the other parts are similar to a normal male. Both palpi are equally developed, but imperfect and anomalous. The tarsus has an alveolar cavity, but the genital bulb elongates cylindrically, without any complicated structure. Paracymbium is on the ectal side of the base of the tarsus, but its shape is simple and much different from a normal one. The abdomen has a scape of epigynum which is not fully developed as in the case of subadult female. Present spider seems to be a male slightly affected by female element, that is to say, this individual may be an intersexuality with a strong predominance of maleness.
2. Tetragnatha praedonia L. KOCH
The spider was collected by Mr. K. Murai at Yamaguchi City, on August 2, 1958. Subadult female. The right chelicera is normal, but the left one is very short, about a half of the right in length. This anomaly seems to be the result of regeneration of the left chelicera that was lost for some reason.
3. Coelotes antri (KOMATSU)
This specimen was collected by Mr. Y. Tarumi at Minoo City near Osaka on September 15, 1966.
This individual is clearly a subadult male, compared with another normal subadult male of the same color and shape as the former, both having been collected at the same place and at the same time. But each palp of the former shows anomalous development.
Left palp: patellal apophysis, tibial apophysis and cymbium are normal as in an adult male, but the genital bulb is not normaly specialized.
Right palp: shorter than the left palp; patellal apophysis is imperfect, and the tibial apophysis is developed anomalously; cymbium is short and thick; genital bulb is abnormal, differing from the left one and also from that of a normal adult male.
This spider may be a kind of abnormal neoteny, but since there is no clear evidence to determine so, it is described here as a case of anomaly of male palp.

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At Akayu-machi and Takahata-machi (the north-eastern part of Yonezawa Basin), Higashiokitama-gun, Yama-gata-ken, Japan, we can see thin white threads and small white masses flow quietly in the blue sky on a fine and windless (or breezy) day, from the end of October to December. It will snow soon after this phenomenon, so people in that district call it “ushering in snow” (Yukimukae).
This phenomenon is the same as gossamer (England) or Babie late (Poland), and is found to by caused by threads of spiders as they migrate in the air. It is only in this district in Japan that spiders are observed to migrate in the air and are given a special designation.
I have observed “ushering in snow” and collected spiders for the past fifteen years.
According to my observation, spiders climb to the tip of the leaves of grass or the tip of sticks toward the end of October (occasionally during September), stretch their legs, raise their hips, and emit the threads. Before the threads are emitted, active movement of spinneret was noticed; that is, spiders shook violently the posterior spinneret and repeated the actions which seemed to serve to spin the threads out from the middle spinneret. The threads are emitted from the middle spinneret first. The anterior and posterior spinneret open outside. It was also observed that the number of the threads increased rapidly before spiders flew up, amounting to ten odd. (On such an occasion, the strings are emitted from the both the anterior and the posterior spinneret, centering around the middle spinneret.) On no occasion did they use their legs.
I recognized twelve families, thirty-nine species of “ushering in snow”, that is, gossamer spiders, and it is easily predicted that the kinds will be increased by further investigation.
Among these spiders, it was found that those that are migratory far outnumber those that are web-spinning, and those spiders that migrate far are mostly migratory.
I have classified these spiders in terms of “their ways of life” and “the stage in their life for flight (young, sub-adult, adult)”, shown them in the graph, and investigated the evolution of spiders.
Spiders migration and scattering with the thread flowing in the air seem to bear a close relation to preservation of spiders both as individuals and as a family, and is regarded as an ecological phenomenon against an internecine struggle or lack of food.
Migratory spiders, such as Thomisidae and Lycosidae, emit the threads actively and migrate in the air, in their prime of life. They are neither saltatorial nor web-spinning.
Salticidae have acquired saltation, which has made it easy for them to catch food necessary for preservation of both individuals and a family. Hence, only a few species of this family migrate in the air when they are young.
On the other hand, those spiders which developed ability in spinning a web became capable of getting food without migration, so they did not need to migrate at all. Only during the periods of young and sub-adult when they cannot make big webs do they seem to show the habit of dispersion through migration in the air.
Small-sized spiders, such as Micryphantidae have not been so evolved as to make big webs, they continue a migratory life and presumably keep the habit of migration in the air even as adults.
I have considered the question why spiders migrate toward the end of autumn in relation to lack of food, and reached the following conclusion. The time when they have plenty of food is the time also for their reproduction and egg-laying, and at such a time no spider migrates, while toward the end of autumn when they lack in food, they set out in migration. Furthermore, an air current is crucial for the flight of spiders, and when one spider can fly

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