June 2, 1905.] 



SCIENCE. 



855 



the limits of an abstract will not permit 

 record of these results. On the whole, no 

 characters observed, appeared to follow the 

 laws of Mendel with any accuracy. For 

 example, black X black have invariably 

 produced black offspring, so far with the 

 white ear lobes persisting. A black J* X 

 barred plymouth 5? among others, pro- 

 duced one male offspring which rather 

 closely resembles a dark Brahma cock. 



Pure white Plymouth Rocks which al- 

 ways produced white offspring when bred 

 together, never produced white offspring 

 when crossed either way with brown Leg- 

 horns, nor did any of the mongrel off- 

 spring, when interbred. The majority of 

 the offspring were barred, the remainder 

 being nondescripts or occasionally black. 

 •Interbreeding this generation resulted in 

 the production of several fowls which were 

 of a pure barred Plymouth Rock type ex- 

 cept for the persistent white ear lobes of 

 Leghorn origin. 



Observations on some Peculiar Habits of 

 the Mole-crickets: W. J. Baumgartner, 

 Kansas University. 



The female of our northern mole-cricket, 

 Gryllotalpa borealis, has quite a loud and 

 distinct chirp. This seems to be used as a 

 means of recognition in their dark burrows. 

 This observation is contradictory to the 

 conclusion of all writers who say only male 

 orthoptera chirp, or stridulate. The fe- 

 male of the Porto Riean species Scopter- 

 isciis didactylus has the same kind of a 

 stridulating organ (much smaller and 

 weaker than that of the male) on its elytra, 

 and so I conclude it also chirps. 



Du Four's gland of 'excretory secre- 

 tion,' which later investigators have con- 

 nected with the copulatory organs, is by 

 my observations and experiments shovm to 

 be an effective protective device. A strongly 

 foetid and very sticky secretion is ejected 

 "with considerable force from the siphon- 



like genito-anal opening. This must repel 

 or retard the most ardent pursuer and so 

 protect the soft abdomen from the rear. 



In the act of copulation these insects 

 assume the relative positions suited to their 

 tunnel-like homes. They tui'n posterior 

 end to posterior end and ventral side to 

 ventral side, the male lying on his back. 

 The sperm is transferred in a spermato- 

 phore. Scopterisctis has a similar pro- 

 tective gland, but its copulation was not 

 observed. 



The chirping of the female, the protective 

 anal secretion and the unusual position of 

 male and female in copulation which dis- 

 tinguish the mole-crickets from the rest of 

 the orthoptera are very evidently adapta- 

 tions to life in underground tunnels. The 

 presence of the spermatophore accounts for 

 the annexed glands in the male Gryllotalpa. 



The Eefiex Theory of Orientation as Ap- 

 plied to the Phototaxis of Ranalia: S. J. 

 Holmes, University of Michigan. 



A Note on the Position of the Temporary 

 Pharynx in the Planarian Embryo: W. 

 C. Curtis, University of Missouri. 

 Mattiesen in his extensive account of the 

 embryology of the European Planaria 

 torva, which has been recently published 

 in the Zeitschrift fiir Wissenschaftliche 

 Zoologie ('04), suggests that my descrip- 

 tion of the orientation of the adult and 

 embryonic pharyngeal structures in P. 

 macidata must have been due to the exam- 

 ination of a single abnormal specimen or to 

 distortion caused by poor fixation. My ob- 

 servation has been confirmed by Bardeen 

 ('02) ; and in another American form, P. 

 simplicissima, Stevens ('04) believes the 

 same orientation to exist, although in this 

 case the early disappearance of the primi- 

 tive or embryonic pharynx makes the mat- 

 ter difficult to establish. Mattiesen finds 

 that in P. torva the adult pharynx appears 



