90 
MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 
NORTH AMERICA— Continued. EUROPE— Continued. 
HYMENOPTERA. 
| Typhlopone clawsii Joseph. Carniola. 
VERTEBRATA. 
PISCES. 
Amblyopsis spelasus DeKay. Mammoth, Wyan¬ 
dotte, and Emerson’s Spring Cave, in a pool 
communicating with [Green?] river. J. R. 
Proctor. Caves and wells in Indiana and 
Kentucky. 
Chologastei• cornutus Agassiz. Subterranean 
streams in Mammoth Cave and 
in Tennessee. 
agassizii Putnam. 
Chologaster papilliferus Forbes. Subterranean 
streams and wells in Illinois. 
Typhliehthys subterraneus Girard. Subterranean 
streams of Kentucky, Tennessee, and Alabama. | 
BATRACHIA. 
I Proteus anguineus Laur. Subterranean waters of oaves 
I in Carniola and Dalmatia. 
VII.—LIST OF N0N-CAVERNIC0L0US BLIND OR EYELESS ANIMALS. 
It may be regarded as a matter of some interest to obtain a rough idea of the number of blind 
or eyeless Arthropoda and yertebrata, which do not live in caves, for comparison with the list of 
cave animals. It will be seen that the lists are nearly of the same extent. 
It will also be seen how very small a proportion the blind, nou-cavernicolous animals of the 
two higher branches of the animal kingdom bear to those of normal vision. There are known to 
be not less than from one to two hundred and fifty thousand species of Arthropods and mammals, 
while the blind forms amount to a very small percentage of this number. 
Before beginning our list we may glance at the groups of lower invertebrates which are eye¬ 
less, being either primitively without any organs of vision, or which belong to groups where all 
the species have become adapted to a stationary or parasitic (internal or external) mode of life. 
Protozoa. Without exception eyeless, though some forms have sensitive “ eye-spOts.” 
Porifera. Without exception eyeless. 
Ccelenterata. Many, perhaps a large proportion, eyeless. 
Echinodermata. All, except Asteroidea, eyeless. 
Polyzoa. All, without any known exception, eyeless. 
BracHopoda. Adult forms eyeless, the larv;e of some having temporary eyes. 
Vermes. Cestoids, Trematoda, and nearly all the other parasitic forms, with Lumbricus, etc., eyeless. 
Mollusca. All fresh-water Lamellibranchiata, and many marine forms, without eyes.* 
* In regard to eyeless Mollusca I applied to Mr. W. H. Dali, who was kind enough to supply me with the follow¬ 
ing information: 
“T° fuI1 y answer y° ur letter W0lll <l take nearly a book of itself. But in a few words I will try to give you an 
answer, such as it is. I do not know of any eyeless Cephalopods. Among the Lainellibrancks the vast majority have 
no eyes; developed eyes are very exceptional, but sense organs sensible to light (but not exactly eyes) have been 
found in several species and may exist in many more. We know the characters of the soft parts in only about one 
species in five thousand, so that it is impossible to generalize with safety. Among Gastropods the majority have 
eyes. The presence or absence of eyes is not of much importance in classification, but their position when present 
is important. One species of a genus may be blind and another have eyes. ' Among littoral species those which 
burrow ini the sand, like Natica, Sigaretus, Bullia, Scaphander, Philine, etc., are very apt to be blind, but others of 
the same habit are not. The Chitonid* are all blind if we look for the eyes in the usual place ; but in certain groups 
there is the wonderful apparatus for seeing through the shell, described by Moseley. Nearly all the Pteropods and 
Janthina are blind. Most of the Heteropods, though leading a similar life, have well-developed, movable eyes. 
