528 PROGRESS OF VETERINARY SCIENCE AND ART. 
towards its upper part. The contractions were rapid, but 
not so manifest as before. Respiration was now laboured ; 
and attempts having been made to cause the calf to swallow 
some milk, this was thrown back again into the mouth, and 
symptoms of suffocation supervened. Four hours before 
death the heart had become of an opaque azure tint, and a 
purplish hue was observed on the visible mucous membranes. 
The very rapid movements of the heart consisted in alter- 
nating dilatations and contractions of its upper and lower 
portions, so that deep grooves divided it into three sacs ; two 
upper ones, the largest, but possessed of thinner parietes, 
dilated, whilst the inferior or median one contracted ; this 
rhythmic action was soon indistinct, and followed by rapid 
oscillating or undulatory movements. Irregular twitchings 
of the external muscles, alternated by tetanic spasms, were 
the last symptoms manifest, and the animal ceased to live 
twenty-five hours after birth. After death the purple tint of 
heart and membranes disappeared. The heart looked much 
like a darkish-coloured muscle. 
The subject was injected, and then carefully examined by 
Professor Alessandrini, who at once looked for the coverings 
of the heart. In the vicinity of the grooves above mentioned, 
he discovered that a thick membrane was covering the organ. 
It was readily opened out, and found to consist of an internal 
fibrous tunic, continuous above with the blood-vessels, and 
which constituted the true pericardium ; the external layer of 
this envelope was an extension of the true skin deprived of 
hair, and which had assumed the soft mucous aspect so 
constantly seen round external apertures of the body, 
where skin is continuous with true mucous membranes. 
The existence of the serous lining to the pericardium could 
only be determined where adhesions had not yet formed. 
Alessandrini believes that if the calf had lived a few more 
hours, the preternatural bond of union between the various 
coverings of the heart, and the heart itself would have been 
complete, and have rendered this case in all like others that 
have been described, and in which the absence of the peri- 
cardium has been looked upon as an essential condition in 
this form of monster. Alessandrini, morever, adds, that 
whoever engages in pathological dissections, both in man 
and the lower animals, will meet with lesions of this kind in 
the adult ; and many cases of absence of the pericardium 
are thus readily explained. 
The more important facts connected with this case were 
revealed on further investigation. The heart was found to 
consist of three cavities ; that is to say, two auricles and a 
