30 



SCIENCE 



[N. S. Vol. XXVII. No. 679 



avidity. This interesting observation indi- 

 cates a narrow food Labit for this species. 



Of the nine remaining larvae of the original 

 lot, five were reared to the adult state. The 

 first pupa appeared March 8, the adult emerg- 

 ing five days later. Thus 179 days had 

 elapsed between the date of collection and the 

 date of pupation, during the last 149 of which 

 the larvae had been without food. 

 ' Among the larvae kept out of doors, which 

 were under nearly natural conditions, the first 

 pupa appeared 196 days after the date of col- 

 lection and the last 201 days. The latter 

 lived 18 days, but the adult failed to emerge. 



This would indicate that under natural con- 

 ditions one would expect the pupae to appear 

 during the latter part of March and most of 

 April and the adults during April and pos- 

 sibly May. 



The average length of the known larval life 

 of the ten individuals which transformed to 

 the pupa state was 196.5 days. The shortest 

 period was 179 days, and the longest 205 days. 

 How much it would be necessary to add to 

 this in order to arrive at the total larval life 

 is not known; nor do we know the incubation 

 period, as we were unable to secure eggs. 



The shortest pupal period was five days, the 

 longest 11 days, and the average 7.3 days. 

 The shortest adult life was one day, the longest 

 11 days, and the average 6.8 days. It is prob- 

 able that with natural conditions the adult 

 stage would have been somewhat lengthened, 

 for this species is rather shy and could not be 

 expected to thrive well under close confine- 

 ment. 



From the fact that a few adults were present 

 when the larvffi were collected, September 10, 

 1906, together with the dates of emergence of 

 those we 'reared, we are led to believe that 

 there are at least two broods per year at this 

 latitude. These broods probably are not 

 sharply defined, because of the variation in 

 time required to hatch the eggs of those mos- 

 quitoes which lay their eggs singly. It is 

 probable that during the latter part of summer 

 all stages may be found together. 



H. A. MORGAJJ 



E. C. Cotton 



DISSOROPHUS — A CORRECTION 



In the American Naturalist for November, 

 1895, Professor E. D. Cope described (p. 998) 

 a new form of Paleozoic amphibian, from the 

 Permian of Texas, which he designated by 

 the name of Dissorophus multicinctus. He 

 based the new form on a series of " ten con- 

 secutive vertebrffi and their appendages " and 

 on account of the peculiar carapace referred 

 to it as a " batrachian armadillo." He char- 

 acterized the new form as follows: 



The neural spines are elevated, and the apex of 

 each sends a transverse branch which extends in 

 an arch on each side to the ribs. These spinous 

 branches touch each other, forming a carapace. 

 Above and corresponding to each of them is a 

 similar dermal osseous element, which extends 

 from side to side without interruption on the 

 median line, forming a dermal layer of transverse 

 bands which correspond to the skeletal carapace 

 beneath it. 



In the Proceedings of the American Philo- 

 sophical Society for May 15, 1896, Cope pub- 

 lished on Plate X. three figures of the same 

 specimen and gave the name as D. articulatus 

 Cope. Again in the American Naturalist for 

 November, 1896, under the title of " Permian 

 Land Vertebrates with Carapaces " (p. 936), 

 he gave additional notes on Dissorophus and 

 repeats the same figures which were given in 

 the Proceedings of the American Philosoph- 

 ical Society, 1896, Plate X., and again gives 

 the name as Dissorophus articulatus Cope. 



In Hay's " Catalogue of the Fossil Verte- 

 brata of North America," there are given two 

 species of Dissorophus, D. multicinctus Cope, 

 and D. articulatus Cope, and reference to the 

 Proceedings of the American Philosophical 

 Society, 1896, Plate X., is omitted. Broili 

 (" Paleontographica," 1904) follows Hay, evi- 

 dently, in making out his list of the Stego- 

 cephalia of the Permian of Texas, since he 

 also gives the two species of Dissorophus. 



There can be no doubt that there is but 

 one species of Dissorophus and that spe- 

 cies is Dissorophus multicinctus Cope first 

 described in 1895. That the specimen first de- 

 scribed is the same as the one figured on Plate 

 X. of the Proceedings of the American Philo- 

 sophical Society, can not be questioned. Cope 



