

The Ohio T^atiiralist, 



PUBLISHED BY 



The Biological Club of the Ohio State Uni'versity, 

 Volume MI, NOVEMBER, 1902. No. 1, 



TABLE OF CONTENTS 



Landacre— Muscular and Skeletal Elements of Pii'.sahis Cornutns 299 



Burr— Ohio Plants witli Dissected Leaves 314 



Riddle— Algae from Sandusky Bay 317 



SCHAFFNER— The Maximum Height of Plants 319 



Landacre— On a Visual Area in Lampsida Ventricosus 320 



Jennings— Meeting of Biological Club 322 



MUSCULAR AND SKELETAL ELEMENTS OF 

 PASSALUS CORNUTUS. 



F. L. Landacre. 



The present paper, on the muscnlar and skeletal elements of 

 Passalus cornntus was begun with a view to determining what 

 changes had arisen in the muscular system in connection with the 

 burrowing habits of the animal. It was found in the course of 

 the study that there was an almost complete atrophy of the mus- 

 cles concerned in flight and a marked hypertrophy of the muscles 

 of the legs ; and that with these changes had arisen certain modi- 

 fijcations in the hard parts to which these muscles are attached. 



These changes in the hard parts were not so numerous or so 

 radical as to justify the rather extended description of the skele- 

 ton, which had been given, if it were not for the fact that the two 

 systems are so intimatelv related and the changes in the one so 

 dependent upon those in the other that constant reference would 

 have to be made to the skeleton. This would be confusing to a 

 reader not entirely familiar with the hard parts. 



The study of these two s}stems led to an investigation of the 

 habits of the insect, especialh- those concerned in distribution and 

 reproduction. 



Passalus is a large black beetle of common occurrence m de- 

 caying logs and stumps which it assists materially in destroying. 

 It can easily be identified by its large size, great strength, sluggish 

 movements and longitudinally striated wing covers. It has a pe- 

 culiar habit of stridulating wdien disturbed. 



It can be secured in great abundance at all times of the year 

 and is easily kept in the laboratory for observation if it is supplied 

 with an abundance of decaying wood. Specimens for dissection 







