AT THE MICROSCOPE. 117 



In the Whelk the lingual band is short, but very strong, and 

 the fore-part closely doubled down to fit it for its own work of an 

 auger. 



These remarks are made to point out that it is necessary, in 

 the study of these mollusc's tongues, to closely investigate arrange- 

 ments connected with the actions of the parts during life, as well 

 as the number, form, and arrangement of the teeth, in which a 

 most inviting field, scarcely touched upon, lies open. 



Bed-Bug, Cimex lectuarius, $ . — This insect, though not a 

 typical Heteropteron, is still, in most respects, a good example of 

 the important Natural order to which it belongs. The peculiar 

 arcuate hairs, serrate on the outer margin of the curve, with three 

 points at the tip, are well shown. In a consideration of the 

 structure of insect hairs they possess considerable value. As 

 special points of interest in this object may be mentioned the 

 various parts of the mouth and some deHcate organs of taste, 

 resembling the " barb-shaped appendages " to Lepidopterous 

 tongues. There are appendages of a very curious nature at the 

 wrist-joints, which are particularly deserving of attention. Their 

 presence or absence and exact structure denote powers of climb- 

 ing over smooth surfaces ; in some instances, the sexes are thus 

 defined, and they furnish recondite characters, easily read by 

 aid of the microscope, whose value will become increasingly 

 apparent as that instrument comes more and more to be applied 

 in a sensible way in the progress of research. 



Tortoise-Tick (PI. XIV.). — From drawings made when 

 this was given to me, I have copied the accompanying figures 

 as well as the remarks attached to the original drawings, 

 I wish to point out the necessity of studying and recording 

 minute details accurately ; the value of this habit will become 

 more evident with every accession of knowledge. For 22 

 years this drawing slept in my portfolio. But the mind had been 

 prepared for the reception of further facts bearing on the subject, 

 and my satisfaction was great when, some seven or eight years ago, 

 the opportunity occurred for examining living specimens. None 

 of the feet in this mounted specimen were perfectly shown, but 

 sufficient appeared to justify the formation of an hypothesis as to 

 their structure, which was recorded in the bit marked " supposed 

 from the above." I thus found what had been a supposition 

 proved to be really correct. 



[Further researches into the general structure and life-history 

 of various ticks is desirable, and we shall be glad to offer facilities 

 for their free discussion. — Ed.] 



