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MOULTING HABITS OF SPIDERS. 103 
side and the door fell back, keeping an attachment to the wall.1 This 
is especially the case with Lycosa tigrina. 
Wagner confirms this observation in the case of the European taren- 
tula, which closes its burrow with a sort of pent house above the door, 
and suspending itself to the sides thereof, head downward, passes its moult. 
In captivity these preparations change in their details, but their aim 
remains the same, and is always attempted in one way or another.” 
It seems probable, as suggested by Wagner, that the nature and extent 
of these precautions depend upon the facility with which the moult is 
accomplished; the greater the facility the less the precaution. 
Facility Wor example, young spiders appear to experience little or no 
ees difficulty in shedding their coats, which they do in a few min- 
: utes—young Orbweavers in from three to ten minutes, young 
Trochosas in two minutes. As the spiders advance in age the succeeding 
moults are passed with increasing difficulty, the last moult being often 
the hardest to achieve. Now, young spiders make no preparations and 
take no precautions in moulting, and drop their skins wherever they 
S chance to be, a carelessness which disappears with the approach 
a of adult life. Thus Wagner records that the young of Trochosa 
epider, singoriensis make no protective defenses during the early period 
of life, when they moult easily; but as the act is made more 
difficult and protracted by advancing age, they cover their burrows when 
they feel the moulting period coming on. 
The Thomisoids quite generally shed their skins easily and rapidly, 
and, accordingly, they do it openly, only spinning a supporting thread 
over the petals of a flower or the surface of a leaf. Even in the case of 
some young spiders one may see evidence of the same sensitiveness to 
danger, for if the young of Attus terrebratus, who are in the habit of 
moulting en masse within the maternal cocoon, be removed after the 
second moult and put in a suitable place, every one will spin a little cell 
within which the third moult is separately made. This quick perception 
of the change of condition and ready adaptation thereto is justly noted 
by Wagner, who relates it as a fine example of instinctive wisdom. 
My tarantula “ Leidy,” distinguished by having reached the greatest age 
of any spider known to science, finally died in the act of moulting when 
more than seven years old, Its death is another example of a fact which 
I had previously observed, that the act of moulting is frequently attended 
by dangers of one kind or another to spiders. It is common to find 
'My Garden Pets, page 82. 
2 One needs to distinguish between the word tarantula, which is the popular name for 
the huge Mygale of our southwestern States, and the genus Tarentula of the Lycosids. The 
Turret spider (L. arenicola) and my Tarentula (Lycosa) tigrina are closely related in habits 
and structure to the famous “tarentula” of Italy, and the well known Tarentula (Lycosa) 
Narbonensis. ; 
