Mr. BrightwcU on Filarice and Insects. 397 



increase, an increase which has been sometimes so great in stagnant 

 waters, as to change them into the appearance of blood, and make them 

 like a thick mass of living water. 



The Daphnice are about the size of a pin's head, and half a dozen 

 Tipulidan larvce will clear a bottle well stocked with them in a few 

 hours. They seize their prey with the rapacity of a Pike, grasping it 

 with the two anterior jaws or hooks (as Reaumur calls them) and gorging 

 it alive. The larger Daphnice, filled with ova, often struggle a long 

 time in the jaws of their adversary, who can only swallow them by 

 degrees. These Zaru^ will live several days without food, but die after 

 that time, although the water be daily changed. Once, being unable to 

 procure any Daphnice, I cut some roasted mutton into small particles, 

 and on putting a few into the bottle in which I kept the larvce, most of 

 them struck at, and two actually gorged, this substantial diet. One of 

 these I kept for some days in a small glass tube, watching it carefully 

 until the mutton had digested. From the transparency of the animal 

 this process might distinctly be perceived ; the food dissolving into an 

 opaque fluid, was gradually absorbed by the surrounding vessels, until 

 the body was tinged with a greenish color. This animal continued in a 

 highly vigorous state for two days without any other food, when it 

 changed first into the nympha state, then into a fine specimen of the 

 perfect insect. 



A bad figure ot this larva is given by Reaumur ; we have given a 

 •nore accurate one, Plate XIX., fig. 1, in which a. is the animal of the 

 natural size and b. highly magnified. In the latter the parts as described 

 by Reaumur will be readily traced. 



II. Most Naturalists are aware of the fact that intestinal worms are 

 found in the bodies of various insects, and particularly in those of several 

 species of the Carahidce inhabiting moist situations. I have found them 

 most abundantly in the bodies of the Harpalus or Molops madidus, a 

 very common insect of this family. These worms, which are identical 

 vnth, or allied to, the Gordius aquaticus, Linn. fFilaria of modern 

 authors), are a most formidable foe to these insects, devouring the 



