Perithecia carbonaceous or membranaceous, sometimes confluent with the stroma, pierced at the apex, and mostly papillate; hymenium diffluent.—Berkeley Outlines.

There are four tribes in this family, viz:

• NectriÆi.
• XylariÆi.
• Valsei.
• SphÆriei.

Under NectriÆi we have the following genera:

Cordyceps. Fr.

Cordyceps is from a Greek word meaning a club and a Latin word meaning a head. It is a genus of Pyrenomycetous fungi of which a few grow upon other fungi, but by far the greater number are parasitic upon insects or their larva, as will be seen in Figure 491.

The spores enter the breathing openings along the sides of the larva and the mycelium grows until it fills the interior of the larva and kills it.

In fructification a stalk rises from the body of the insect or larva and in the enlarged extremity of this the perithecia are grouped. The stroma is vertical and fleshy, head distinct, hyaline or colored; sporidia repeatedly divided and sub-moniliform.

Cordyceps Herculea. (Schw.) Sacc.

Herculea is so called from its large size. The halftone will readily identify this species. The plant is quite large, clavate in form, the head oblong, round, slightly tapering upward with a decided protuberance at the apex, as will be seen in Figure 491. The head is a light yellow in all specimens I found, not alutaceous as Schw. states, nor is the head obtuse. I found several specimens on a sidehill in Haynes's Hollow in August and September, all growing from bodies of the large white grubs which are found about rotten wood. They were found during wet weather. They were identified by both Dr. Peck and Dr. Herbst.

Cordyceps militaris. Fr.

This is much smaller and more common than C. Herculea. Conidia—SubcÆspitose, white; stem distinct, simple, becoming smooth; clubs incrassated, mealy; Conidia globose. Ascophore—Fleshy, orange-red; head clavate, tuberculose; stem equal; sporidia long, breaking up into joints. This is frequently called Torrubia militaris.

It is known as the caterpillar fungus. Its spores are cylindrical and are produced upon orange-red fruiting bodies in the fall. As soon as the spore falls on the caterpillar it sends out germ-threads which penetrate the caterpillar. Here the threads form long narrow spores which break off and form other spores until the body-cavity is entirely filled. The caterpillar soon becomes sluggish and dies. The fungus continues to grow until it has completely appropriated all of the insect's soft parts, externally a perfect caterpillar but internally completely filled with mycelial threads. Under favorable conditions this mycelial caterpillar, which has become a storage organ, will send up an orange-red club-shaped body, as will be seen in Figure 492, and will produce the kind of spores described above. Under some conditions this mycelial caterpillar may be made to produce a dense growth of threads from its entire surface, looking like a small white ball, and from these threads another kind of spore is formed. These spores are pinched off in great numbers and will germinate in the larva the same as the sac spore. The specimens were found by Mrs. E. B. Blackford near Boston, and photographed by Dr. Kellerman.

Cordyceps capitata. Fr.

This plant is fleshy, capitate, head ovate, bay-brown, stem yellow, then blackish.

This plant is parasitic on Elaphomyces granulatus. It is shown at the base of the stem of the plant. It grows two or three inches under the surface and somewhat resembles a truffle in appearance.

Both are very interesting plants. The plant in Figure 493 was found near Boston, Mass. They are usually found in pine woods, often in tufts. The stems are from one to four inches long, nearly equal, smooth, lemon-colored, at length fibroso-strigose and blackish.

It is sometimes called Torrubia capitata.