352 



and tlie author's large reprint has just reached us. While we are not 

 deeply versed in the subject ot insect embryology, this work strikes us 

 as a very able production. It covers 148 pages and is illustrated by 

 six large folding plates. The subjects treated are: The embryonic de- 

 velopment of the Locustidte; Gastrulation in the Orthoptera; the in- 

 dusium and its homologues in the Arthropoda ; General considerations 

 of the embryonic envelopes and revolution of the insect embryo ; IsTeuro- 

 genesis in the lusecta ; the development of the reproductive organs in 

 the Insectaj the subcesophageal body in Xiphidium and Blatta: Tech- 

 nique; Bibliography. The species among the Locustidse to which he 

 has devoted his principal attention ave Xix^Jiidium ensiferum and Or- 

 clieUmum vulgarej and certain biologic facts of interest concerning each 

 species are placed on record incidentally to the main purpose of the 

 work. He has made the Orthoptera a starting point in his studies, with 

 a view of determining their relations to the Apterygota on the one hand 

 and to the higher orders on the other; for, although the primitive and 

 synthetic character of the Orthoptera has been recognized by com- 

 parative anatomists, the full importance of the group, according to Dr. 

 Wheeler, has been but little appreciated from the embryological stand- 

 point. 



INSECTS SAID TO FORECAST THE ^T:ATHEE. 



In reply to our suggestion on page 138 of the current volume our val- 

 ued correspondent. Mrs. M. E. Eice, of Ooryville, Pa., sends us the fol- 

 lowing local ideas concerning insects and the weather: 



It is a common superstition here that the llaclc markings on the larvcB of Fyrrharc- 

 tiaisaheUa, or '' Wooly Bear '^ as it is commonly called, foretell the severity of the 

 weather during- the winter. If the black is longest on the head end the forepart of 

 winter willbe seA'eiest, and if rR-erersrt. then scoring will be coldest. Now some of 

 the larvje are WacJc at both ends, some either one or the other end, while some are not 

 J/acA- at all, or faintly marked. Whether this variation is owing to sex or food or envi- 

 ronment I know not. A continuous flight of Dragon flies is said to portend a wet 

 spell (I should say follow a dry spell). Observation shows that a sudden inroad of 

 flies is a portent of rain. Spiders lie dormant in winter; before a thaw they liven 

 up. An irruption of black ants in my house when the thermometor has for weeks 

 hovered below zero, means to my mind an open spring. Such an one occurred last 

 20th of February and caused me to prophesy mild weather. I was derided, as we 

 generally have '"'six weeks winter m March " here, but events proved that I was 

 correct. Snails (spiral snails) crawl about only on the approach of wet or cloudy 

 weather. You may expect rain in six hours from their appearance. 



WHAT CONSTITUTES A SPECIES. 



One of our corresi^ondents who is just beginning the study of system- 

 atic entomology has receutly written us inquiring what constitutes a 

 species. To this inquiry we have made the following answer: 



Your question regarding what constitutes a species is a broad one and not easy 'to 

 answer in brief. In the abstract, a species is limited by the capacity of its individ- 

 uals of both sexes to couple and produce fertile otfspring, and to continue this indefi- 



