148 BERTRAM G. SMITH. 



caused by the diffusion of light passing through these concentric 

 lavers tangential to their inner surfaces. The core or axis of the 



* o 



connecting cord also has the same milky appearance, due to a 

 continuation of the lamellar structure. 



The outer surface of the capsule and cord is, to ordinary 

 observation, perfectly smooth and regularly rounded when the 

 material is in fresh condition. But a careful examination, espe- 

 cially with the aid of a lens, reveals a delicate longitudinal stria- 

 tion due to fine parallel grooves or scratches separated by nearly 

 equal intervals. This structure is too minute to be represented 

 in Fig. i. In some portions of the string the striae have a 

 slightly spiral direction about the axis of the cord and capsule. 

 The striae appear as they would if made by the scratching of the 

 surface of the envelope against the teeth of a fine comb ; perhaps 

 they are caused by friction of the envelope against papillae of 

 some sort in the lower portion of the oviduct or in the cloaca, 

 while the gelatinous material is yet soft. 



After the eggs have been in water for several days, or after 

 preservation in formalin or alcohol, the outer layer of the egg 

 envelope becomes cast into conspicuous wavy folds or wrinkles of 

 a different nature from the striae noted above. These folds ap- 

 pear first at the ends of the connecting cord adjacent to the egg 

 capsule and have here a strongly marked spiral arrangement, 

 suggestive of the chalazae of the hen's egg (see Fig. i) ; later the 

 folding may extend over the capsule and the middle of the cord, 

 but seldom with so regular a spiral arrangement in these regions. 

 Sometimes the spiral is continuous from one capsule to another. 

 As a rule the spiral is constant in the direction in which it ex- 

 tends about the axis in all portions of the cord and capsule. 



The inner layer of the lamellar core of the cord in some cases 

 exhibits a marked twisted or spiral arrangement like that of the 

 inner portion of the cord connecting the eggs of Iclitliyopliis as 

 described by the Sarasins ('87 '93 ). 



The following measurements were taken : 



1 i ) Diameter of egg proper, 7 mm. 



(2) " " " with envelopes, 18 " 



(3) " connecting cord, 5 " 



(4) Distance from one egg to another, measured from 



center to center, 3 cm. 



