. The elements of insect anatomy; an outline for the use of students in entomological laboratories. insect wings there exists a type of branching which is very different from that of our hypothetical primitive type. An examination of Figure 5, which represents the latter, will show that in every case the forked veins are branched dichoto- mously, while in the many-veined wings the more character- istic type of branch- ing results in the formation of pecti- nate veins; this pectinate type of branching is well shown by the cubi- tus in a cockroach (Fig. ro Cu). The changes that take place in the
. The elements of insect anatomy; an outline for the use of students in entomological laboratories. insect wings there exists a type of branching which is very different from that of our hypothetical primitive type. An examination of Figure 5, which represents the latter, will show that in every case the forked veins are branched dichoto- mously, while in the many-veined wings the more character- istic type of branch- ing results in the formation of pecti- nate veins; this pectinate type of branching is well shown by the cubi- tus in a cockroach (Fig. ro Cu). The changes that take place in the development of the pectinate type of venation from the dichotomous type are of two kinds : first, the develop- ment of accessory veins ; second, the modification of the primitive veins so that they are no longer dichotomously branched. The former has been dis- cussed above.; we will now briefly refer to the latter. For this purpose we will give a series of diagrams illustrating. FIG. ii.—Diagrams of several types of Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Comstock, John Henry, 1849-1931. Ithaca, N. Y. , Comstock Pub. Co.
Size: 1165px × 2145px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorcomstock, bookcentury1900, bookdecade1910, bookyear1910
