154 INTRODUCTION TO ZOOLOGY. 



instantaneously loses all her activity, seems paralysed, and 

 coils her tremulous limbs, as if mortally wounded : if the bag 

 be returned, her ferocity and strength are restored the moment 

 she has any perception of its presence, and she rushes to her 

 treasure to defend it to the last." 



We now close our notice of the Articulated animals. We 

 have spoken of Worms, Barnacles, Crabs, Insects, and Spiders; 

 to common observers a motley and unattractive group. Yet, 

 how varied in their structure! how wondrous in their habits! 

 To the humble-minded and patient observer, they are sug- 

 gestive of ideas and emotions too multiplied and fugitive to 

 be embodied in words, but affording an example of the truth 

 so beautifully expressed by the poet: — 



" The air in which we breathe and live, 



Eludes our touch and sight; 

 The fairest flowers their fragrance give, 



To stilkiess and to night: 

 The softest sounds that music flings, 

 In passing from her heaven-plumed wings, 



Are trackless in their flight! 

 And thus life's sweetest bliss is known 

 To silent, grateful thoughts alone." — B. Barton. 



Note. — 1854. Aphides, page 141. The terms " virgin 

 aphides" and " larva state'' can no longer be considered stricUy 

 applicable. The successive broods owe their origin not to female 

 aphides, but to sexless individuals which are capable of repro- 

 duction by a process of budding. " The germs," to use the words 

 of Dr. Burnet, "are situated in moniliform rows, like the suc- 

 cessive joints of confervoid plants, and are not enclosed in a 

 special tube." " What interpretation shall we put on these 

 reproductive parts — these moniliform rows of germs ?' ' Ignoring 

 all existing special theories relating to reproduction, the ob- 

 serving physiologist would be left no alternative but to regard 

 them as buds, true gemmce, which sprout from the interior surface 

 of the aphis, exactly like buds, from the external skin of a 

 Polype." — Dr. Burnett on the development of viviparous aphides. 

 American Journal of Science and Arts. January, 1854. 



