1916 Pomona Journal of Entomology and Zoology, Vol VUI, No. 1, Mar. 



The Life History of Anoplodactylus 

 Erectus Cole 



WILLIAM A. HILTON 



As an Introduction to the statement of the life history of this 

 species it may be worth while to briefly review something of the 

 literature on the subject and follow this with all that is known of 

 our Californian or Laguna Beach forms. 



The fact that the males carry the eggs after laying was first 

 determined by Cavanna in 1877. The eggs are large or smaller 

 according to the yolk present. In PhoxichiUdium and Tanystyliim 

 studied by Morgan, the eggs are .05 mm., in Paleiie, .25 mm. In 

 certain species of Nymphon they have been described as large as 

 .5 to .7 mm. in diamater, Dohrn, '81. The egg masses are one or 

 more for each leg. In Paloie there are only two eggs in each group, 

 but according to Dohrn there may be a hundred or more in each 

 bunch. In some cases both legs hold a single mass. Segmentation 

 is complete and equal in the smaller eggs, unequal in the larger. 

 The best account of the later development is given by Meisenheimer 

 for Ammothea in 1902. A typical gastrula is formed by an in- 

 growth of cells from the uniform almost solid previous stage. This 

 gastrula however has no cavity, but later it forms into midgut and 

 dorsal and lateral parts, the sources of the heart, muscles and con- 

 nective tissues. Later there is a longitudinal germ band about the 

 yolk and in this, paired thickenings appear which represent the 

 cerebral and subesophageal ganglia, lateral thickenings mark the 

 point of origin of the appendages. The chelifori are the first to 

 appear. In Palcue (Morgan) the fourth leg is next, then the fifth 

 and sixth. The third and seventh come just before hatching. 



Palenc and some other forms such as some species of Nymphon 

 have in the larva all of the appendages of the adult, but most free 

 larvcT are provided with three pairs of appendages. Such are called 

 protonymphon stages. In various species these appendages differ 

 somewhat, but in practically all, the body is similar at first. The 

 body during early larval stages is roughly circular in outline, the 



