t9i-- CoLGAN. — Devclopviait of Actacoma. 229 



appear to have ceased with the issue of the embryo from 

 the egg, I give here some details of the subsequent develop- 

 ment of the young Actaeonia in the belief that they may 

 add something to our knowledge of the subject. 



It should be premised here that the egg-cluster of Actae- 

 onia consists of three envelopes. Outside of all is a rather 

 amorphous gelatinous mass, next comes an elastic trans- 

 lucent membrane closely embracing the eggs, and, finally, 

 within this, the individual egg-cases or shells enclosing the 

 orange -coloured yolk suspended in a milky albumen. As 

 development proceeds — usually within 6 days after depo- 

 sition of the cluster — this albumen becomes absorbed so 

 as to leave the extra-embryoni cregion of the egg quite 

 clear. In the egg-cluster just referred to, hatched out on 

 the 19th March, the embryos, with the eyes and mouth well 

 developed and dark brown pigment scattered over the 

 yellowish background of the body, were found to have 

 emerged from their individual shells 4 days before they 

 succeeded in forcing their way through the tenacious 

 general envelopes. Their strivings after freedom were 

 interesting to watch, as the young animals crawled over 

 each other with serpentine flexibihty. Now and then one 

 of the larger individuals, for they varied a good deal in 

 size, would thrust against the viscous envelope until his 

 head and ^ houlders w^ere protruded. But the effort was not 

 sustained ; and the head would retire. From time to 

 time a combined attack would be made on the prison walls, 

 the efforts of the leader being supported by a thrust from 

 behind by three or four of his fellow-captives, until the 

 membrane was seen to bag outwards in a way that threat- 

 ened complete rupture. The first of the infant Actaeonias 

 left its individual shell at 10 p.m., on the 15th March, and 

 all were out on the following morning ; but it was not until 

 6.30 p.m. on the 19th, that the first broke free from the 

 general envelopes, whence the last issued on the morning 

 of the 20th. 



No sooner had the young Actaeonias gained their freedom 

 than they showed all the precocity of the freshly-hatched 

 chick of the barn-door fowl. A few minutes after emergence 

 several were seen to crawl on to some sprays of the green 



