Spiders 



spider. As we have remarked, the number of spinnerets 

 varies, but in the case of this spider we find that there are 

 three pairs. Some spiders possess but a single pair, others 

 are rich in the possession of four pairs. Each spinneret 

 consists of a little knob, studded at its tip with a number 

 of fine tubes and a few larger tubes called spigots. These 

 tubes and spigots are merely the external openings of 

 silk glands, of which there are about six hundred in the 

 garden-spider. Imagine, in the relatively small spider's 

 body, six hundred little factories all turning out silk at 

 top speed ! 



The spinnerets of the garden-spider are arranged in 

 three groups. The pair of spinnerets nearest the head 

 each bear a single spigot, the middle pair bear three 

 spigots each, and each of the hind pair bears five spigots. 

 To these must be added at least a hundred of the smaller 

 tubular openings in each spinneret, giving a total of 

 eighteen spigots and six hundred smaller tubes to each 

 spider. Six hundred and eighteen little openings all able 

 to turn out the work of the six hundred odd silk factories 

 in the body of the garden-spider ! Each opening is 

 capable of giving off silk, though this is never done indis- 

 criminately and the silk from the different openings is not 

 all of the same quality. 



For the silk of the foundation lines of their webs strong 

 threads are required and obtained from the pair of spigots 

 on the spinnerets nearest the head. When, as occasionally 

 happens, still stronger silk is required, additional threads 

 are supplied by a single spigot on either of the middle 

 spinnerets. The remaining four middle spigots, together 

 with four of the spigots on the hinder spinnerets, supply 

 the stronger but less elastic silk which is used in the 

 construction of cocoons and never for the weaving of 

 snares. This leaves us with six hinder spigots to be 

 accounted for and they, again, supply silk of a peculiar 

 nature. We have mentioned that silk issues in a semi- 

 liquid state and hardens in contact with the air. Here, 



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