528 Wisconsin Academy of Sciences, Arts, and Letters. 



bead is miicli reduced. The eyes are absent on this right head, 

 but two slits possibly representing orbits are found lateral to the 

 parietal plates. The left side of the lower jaw of the left 

 head is also deficient. 



Case XIII. This is either an embryonic or very young 

 Tropidonotus fasciata sipedon Linn. [Plate XXXYIII, Fig. 

 13]. The inner side of the left head is deficient, there being 

 no eye. A sharp angle is noticeable in the vertebral column re- 

 jsembling very much that of Case VIII. Somewhat farther 

 ■caudad is a loop with the ventral surfaces inward and mutually 

 coalesced. Cephalad to this loop is a median deficiency in the 

 gastrosteges making an opening into the abdominal cavity. 

 The number of longitudinal rows of scales is variable, for 

 rows begin and end at several points along the body. The 

 angle of the frontal planes is about 90°. 



It might be well at this point to put on record other cases of 

 two-headed snakes which were described in the popular press 

 or Avhich were seen by the author but were not made tlie sub- 

 ject of detailed stud v. 



Mr. Outran! Bangs had a young Tropidonotus fasciata 

 ■sipedon Linn, which he had collected at Stoneham, Mass. In 

 degree of bifurcation it resembled the individual described 

 above as Case II. 



In the Scientific American of December 5, 1896, is an ar- 

 ticle describing a double-headed snake and illustrated by a 

 cut from a photograph. It is said to be a Heterodon simus 

 Linn, from Central America. But since this locality is outside 

 the range of the species as given by (Jope, it is probably wrong. 

 From the cut the degree of bifurcation seems to approximate 

 that of Case VI. in this paper. 



A two-headed snake was advertised on exhibition in a cisrar 

 store in XeAv York in 1896 or 1897. The owner, Mr. 11. C. 

 Somers, told me that after the snake died, it had been de- 

 stroved. It v/as found in the Catskills, though attributed in 

 .•an advertisement to South America. I believe that this was 

 the snake described in the Scientific American. 



A two-headed snake was found near the Xew York Zoologi- 

 cal Park in 1901. The Xew York Tribune said it w^as a 



