464 THE INVERTEBRATA 



There are no tarsi on the legs, claws being borne by the tibiae. The 

 I St abdominal segment carries a ventral tube which is moistened by 

 a glandular secretion from behind the labium poured down a ventral 



Fig. 321. Lepisma saccharina. Fig. 

 From Imms, after Lubbock. 



322. Machilis (Petrobius) maritimus. 

 From Imms, after Lubbock. 



groove running along the middle of the thorax. This ventral tube, re- 

 garded as adhesive, is formed by the fusion of the embryonic append- 

 ages of this segment. On the ventral side of the 3rd segment, the 



